Epson | RX-8801SA/JE | User manual | Application Manual

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ETM26E-03

Application Manua

l

Real Time Clock Module

RX-8801SA/JE

NOTICE

• The material is subject to change without notice.

• Any part of this material may not be reproduced or duplicated in any form or any means without the written permission of Epson Toyocom.

• The information, applied circuit, program, usage etc., written in this material is just for reference.

Epson Toyocom does not assume any liability for the occurrence of infringing any patent or copyright

of a third party. This material does not authorize the licensing for any patent or intellectual copyrights.

• Any product described in this material may contain technology or the subject relating to strategic

products under the control of the Foreign Exchange and Foreign Trade Law of Japan and may require an

export licence from the Ministry of International Trade and industry or other approval from another

government agency.

• You are requested not to use the products (and any technical information furnished, if any) for the

development and/or manufacture of weapon of mass destruction or for other military purposes.

You are also requested that you would not make the products available to any third party who may

use the products for such prohibited purposes.

• These products are intended for general use in electronic equipment. When using them in specific

applications that require extremely high reliability such as applications stated below, it is required to

obtain the permission from Epson Toyocom in advance.

/ Space equipment (artificial satellites, rockets, etc) / Transportation vehicles and related (automobiles,

aircraft, trains, vessels, etc) / Medical instruments to sustain life / Submarine transmitters

/ Power stations and related / Fire work equipment and security equipment / traffic control equipment

/ and others requiring equivalent reliability.

• In this manual for Epson Tyocom, product code and marking will still remain as previously

identified prior to the merger.Due to the on going strategy of gradual unification of part numbers, please

review product code and marking as they will change during the course of the coming months.

We apologize for the inconvenience, but we will eventually have a unified part numbering system

for Epson Toyocom which will be user friendly.

RX - 8801 SA / JE

Contents

1. Overview.......................................................................................................................... 1

2. Block Diagram ................................................................................................................. 1

3. Terminal description ........................................................................................................2

3.1. Terminal connections........................................................................................................................2

3.2. Pin Functions ....................................................................................................................................2

4. Absolute Maximum Ratings ............................................................................................. 3

5. Recommended Operating Conditions.............................................................................. 3

6. Frequency Characteristics ............................................................................................... 3

7. Electrical Characteristics ................................................................................................. 4

7.1. DC Characteristics............................................................................................................................4

7.2. AC Characteristics ............................................................................................................................5

8. Use Methods.................................................................................................................... 6

8.1. Overview of Functions ......................................................................................................................6

8.2. Description of Registers....................................................................................................................7

8.2.1. Register table .....................................................................................................................7

8.2.2. Control register (Reg F)......................................................................................................8

8.2.3. Flag register (Reg-E) ........................................................................................................10

8.2.4. Extension register (Reg-D) ...............................................................................................11

8.2.5. RAM register (Reg - 7) .....................................................................................................12

8.2.6. Clock counter (Reg - 0 ∼ 2)...............................................................................................12

8.2.7. Day counter (Reg - 3) .......................................................................................................12

8.2.8. Calendar counter (Reg 4 to 6) ..........................................................................................13

8.2.9. Alarm registers (Reg - 8 ∼ A)............................................................................................13

8.2.10. Fixed-cycle timer control registers (Reg - B to C) ...........................................................13

8.3. Fixed-cycle Timer Interrupt Function...............................................................................................14

8.3.1. Diagram of fixed-cycle timer interrupt function..................................................................14

8.3.2. Related registers for function of time update interrupts. ...................................................15

8.3.3. Fixed-cycle timer interrupt interval (example) ...................................................................16

8.3.4. Fixed-cycle timer start timing ............................................................................................16

8.4. Time Update Interrupt Function ......................................................................................................17

8.4.1. Time update interrupt function diagram ............................................................................17

8.4.2. Related registers for time update interrupt functions. .......................................................18

8.5. Alarm Interrupt Function .................................................................................................................19

8.4.1. Diagram of alarm interrupt function ..................................................................................19

8.5.2. Related registers ..............................................................................................................20

8.5.2. Examples of alarm settings...............................................................................................21

8.6. Reading/Writing Data via the I2C Bus Interface..............................................................................22

8.6.1. Overview of I2C-BUS .......................................................................................................22

8.6.2. System configuration ........................................................................................................22

8.6.3. Starting and stopping I

2

C bus communications ................................................................23

8.6.4. Data transfers and acknowledge responses during I2C-BUS communications ................24

8.6.5. Slave address...................................................................................................................24

8.6.6. I

2

C bus protocol ................................................................................................................25

8.7. Backup and Recovery.....................................................................................................................26

8.8. Connection with Typical Microcontroller..........................................................................................27

8.9. When used as a clock source (32 kHz-TCXO) ...............................................................................27

9. External Dimensions / Marking Layout ..........................................................................28

10. Application notes ......................................................................................................... 30

RX − 8801 SA / JE

I 2 C-Bus Interface Real-time Clock Module

RX − 8801

SA / JE

• Features built-in 32.768 kHz DTCXO, High Stability.

• Supports I 2

C-Bus's high speed mode (400 kHz)

• Alarm interrupt function for day, date, hour, and minute settings

• Fixed-cycle timer interrupt function

(Seconds, minutes) • Time update interrupt function

• 32.768 kHz output with OE function

• Auto correction of leap years

• Wide interface voltage range: 2.2 V to 5.5 V

• Wide time-keeping voltage range:1.6 V to 5.5 V

(FOE and FOUT pins)

(from 2000 to 2099)

• Low current consumption: 0.8

μ A / 3 V (Typ.)

The I 2 C-BUS is a trademark of NXP Semiconductors.

1. Overview

This module is an I

2

C bus interface-compliant real-time clock which includes a 32.768 kHz DTCXO.

In addition to providing a calendar (year, month, date, day, hour, minute, second) function and a clock counter function, this module provides an abundance of other functions including an alarm function, fixed-cycle timer function, time update interrupt function, and 32.768 kHz output function.

The devices in this module are fabricated via a C-MOS process for low current consumption, which enables long-term battery back-up.

All of these many functions are implemented in SOP-14 pin and VSOJ-20 pin package.

2. Block Diagram

32kHz

DTCXO

32.768 kHz

FOUT

FOE

/ INT

SCL

SDA

DIVIDER

FOUT

CONTROLLER

INTERRUPT

CONTROLLER

I2C-BUS

INTERFACE

CIRCUIT

CLOCK and

CALENDAR

TIMER

REGISTER

ALARM

REGISTER

CONTROL

REGISTER and

SYSTEM

CONTROLLER

Page - 1 ETM26E-03

RX − 8801 SA / JE

3. Terminal description

3.1. Terminal connections

RX − 8801 SA RX − 8801 JE

1. T1 (CE) 14. N.C.

1. /INT 20. N.C.

2. GND 19. N.C.

3. T2 (V

PP

)

# 1

18. N.C.

4. SDA 17. N.C.

15. N.C.

7. SCL 14. N.C.

6. V

DD

9. N.C.

# 11

7. FOE 8. N.C.

10. FOE

SOP − 14pin VSOJ − 20pin

3.2. Pin Functions

Signal name

11. V

DD

I/O Function

SCL Input This is the serial clock input pin for I

2

C Bus communications.

This pin's signal is used for input and output of address, data, and ACK bits, synchronized with the serial clock used for I

2

C communications.

Since the SDA pin is an N-ch open drain pin during output, be sure to connect a suitable pull-up resistance relative to the signal line capacity.

This is the C-MOS output pin with output control provided via the FOE pin.

FOUT Output "H" (high level), this pin outputs a 32.768 kHz signal.

When output is stopped, the FOUT pin = "Hi-Z"( high impedance ).

/ INT

TEST

T1 (CE)

T2 (V

PP

)

V DD

GND

N.C.

Output

Input * Use by the manufacture for testing. ( Do not connect externally.)

Input * Use by the manufacture for testing. ( Do not connect externally.)

This is an input pin used to control the output mode of the FOUT pin.

FOUT pin is stopped.

This pins is used to output alarm signals, timer signals, time update signals, and other signals. This pin is an open drain pin.

* Use by the manufacture for testing. ( Do not connect externally.)

This pin is connected to a positive power supply.

This pin is connected to a ground.

This pin is not connected to the internal IC.

Leave N.C. pins open or connect them to GND or V

DD

.

Note: Be sure to connect a bypass capacitor rated at least 0.1 μF between V

DD

and GND.

Page - 2 ETM26E-03

RX − 8801 SA / JE

4. Absolute Maximum Ratings

Item Symbol Condition Rating

GND = 0 V

Unit

Supply voltage

Input voltage (1)

Input voltage (2)

Output voltage (1)

Output voltage (2)

V DD Between −0.3 to +6.5 V

V

IN1

FOE −0.3 to V

DD

+0.3 V

V

IN2

SCL and SDA pins GND −0.3 to +6.5 V

V

OUT1

FOUT GND −0.3 to V

DD

+0.3 V

V

OUT2

SDA and /INT pins GND −0.3 to +6.5 V

Storage temperature T

STG

When stored separately, without packaging

5. Recommended Operating Conditions

Item Symbol Condition Min.

−55 to +125

Typ. Max.

°C

GND = 0 V

Unit

Operating supply voltage V

DD

Temp. compensation voltage

Clock supply voltage

Operating temperature

V

TEM

Temperature compensation voltage

1.6 3.0 5.5 V

2.2 3.0 5.5 V

V

CLK

− 1.6 3.0 5.5 V

T

OPR

No −40 +25 +85 °C

6. Frequency Characteristics

Item Symbol Condition Rating

GND = 0 V

Unit

Ta= 0 to +40 °C, V

DD

=3.0 V

Ta= −40 to +85 °C, V

DD

=3.0 V

± 1.9

( ∗1)

± 3.4

( ∗2)

Frequency stability Δ f / f

U A

× 10 −6

U B

Ta= 0 to +50 °C, V

DD

=3.0 V

Ta= −40 to +85 °C, V

DD =3.0 V

± 3.8

(

± 5.0

(

∗3)

∗4)

Frequency/voltage characteristics f / V Ta= +25 °C, V

DD

=2.2 V to 5.5 V ± 1.0 Max. × 10 −6 / V

Oscillation start time t STA

Ta= +25 °C, V

DD

=1.6 V

Ta= −40 to +85 °C, V

DD

=1.6 V to 5.5 V

1.0 Max.

3.0 Max. s

± 3 Max. × 10 −6 / year Aging fa °C, V

DD

=3.0 V, first year

* 1 ) Equivalent to 5 seconds of month deviation. * 2 )

* 3 ) Equivalent to 10 seconds of month deviation. * 4 )

Equivalent to 9 seconds of month deviation.

Equivalent to 13 seconds of month deviation.

Page - 3 ETM26E-03

RX − 8801 SA / JE

7. Electrical Characteristics

7.1. DC Characteristics *Unless otherwise specified, GND = 0 V, V

DD

= 1.6 V to 5.5 V, Ta = −40 °C to +85 °C

Item Symbol Condition

Current consumption (1)

Current consumption (2)

Current consumption (3)

Current consumption (4)

Current consumption (5)

Current consumption (6)

Current consumption (7)

Current consumption (8)

Current consumption (9)

Current consumption (10)

I DD1

I

DD2

I

DD3

I DD4

I

DD5

I

DD6

I

DD7

I DD8

I

DD9

I

DD10

f

SCL

= 0 Hz, / INT = V

DD

FOE = GND

FOUT : output OFF ( High Z )

Compensation interval 2.0 s

f

SCL

= 0 Hz, / INT = V

DD

FOE = V DD

FOUT :32.768 kHz, CL =0pF

Compensation interval 2.0 s

f

SCL

= 0 Hz, / INT = V

DD

FOE = V

DD

FOUT :32.768 kHz, CL =30pF

Compensation interval 2.0 s

f

SCL

= 0 Hz, / INT = V

DD

FOE = GND

FOUT : output OFF ( High Z )

Compensation OFF

f SCL = 0 Hz, / INT = V DD

FOE = GND

FOUT : output OFF ( High Z )

Compensation ON ( peak )

V

DD

= 5 V

V DD = 3 V

V DD = 5 V

V

DD

= 3 V

V

DD

= 5 V

V DD = 3 V

V

DD

= 5 V

V

DD

= 3 V

V DD = 5 V

V

DD

= 3 V

High-level input voltage

Low-level input voltage

High-level output voltage

Low-level output voltage

V

IH

V OH3

V

OL1

V

OL2

V

OL3

FOE pin

SCL and SDA pins

FOE pin

V

V

V

V

V

V IL

OH1

OH2

OL4

OL5

OL6

SCL and SDA pins

FOUT pin

V DD =5 V, I OH = −1 mA

V

DD

=3 V, I

OH

= −1 mA

V

DD

=3 V, I

OH

= −100 μA

V

DD

=5 V, I

OL

=1 mA

FOUT pin

/ INT pin pin

V

DD

=3 V, I

OL

=1 mA

V DD =3 V, I OL =100 μA

V DD =5 V, I OL =1 mA

V

DD

=3 V, I

OL

=1 mA

V

DD

≥2 V, I

OL

=3 mA

Input leakage current

Output leakage current

I LK FOE, SCL, SDA pins , V IN = V DD or GND

I

OZ

/ INT, SDA, FOUT pins, V

OUT

= V

DD

or GND

• Temperature compensation and consumption current

1.2 3.4

μA

0.8 2.1

3.0 7.5

μA

2.0 5.0

8.0 20.0

1.15 2.95

μA

μA

GND

GND

0.8 × V

DD

0.7 × V

DD

− 0.3

− 0.3

430 900

V DD + 0.3

0.2 × V

DD

0.3 × V

DD

μA

V

4.5 5.0

2.9 3.0

GND GND+0.5

GND GND+0.8 V

GND

GND

−0.5

−0.5

GND+0.25

GND+0.4

V

Compensation ON

0.977 ms

I DD9,10

I DD7,8

Compensation OFF

Compensation interval ( 2.0 s )

Average

I

DD1,2

Page - 4 ETM26E-03

RX − 8801 SA / JE

7.2. AC Characteristics

SCL clock frequency

Start condition setup time

Start condition hold time

Data setup time

Data hold time

Stop condition setup time

Bus idle time between start condition and stop condition

Time when SCL = "L"

Time when SCL = "H"

Rise time for SCL and SDA

Fall time for SCL and SDA

Allowable spike time on bus

FOUT duty

Timing chart

Protocol

START

CONDITION

(S) t

SU ; STA

BIT 7

MSB

(A7) t

LOW t

HIGH

* Unless otherwise specified,

GND = 0 V , V

DD

= 1.8 V to 5.5 V , Ta = −40 °C to +85 °C

Min. Unit f

SCL t

SU;STA

0.6 t

HD;STA t

SU;DAT t

HD;DAT t

SU;STO

0.6

100

0

0.6

μs

μs ns

μs t BUF 1.3 μs t

LOW t HIGH t r t f t

SP t

W

/t

1.3

0.6

μs

μs

50% of V

DD level 40 50 60 %

BIT 6

(A6)

1 / f

SCL

BIT 0

LSB

(R/W)

ACK

(A)

STOP

CONDITION

(P)

START

CONDITION

(S) t

SU ; STA

SCL

(S) (P) (S) t BUF t r t f

SDA

(A) t HD ; STA t SU ; DAT t HD ; DAT t SP t SU ; STO t HD ; STA

Caution: When accessing this device, all communication from transmitting the start condition to transmitting the stop condition after access should be completed within 0.95 seconds.

If such communication requires 0.95 seconds or longer, the I

2

C bus interface is reset by the internal bus timeout function.

Page - 5 ETM26E-03

RX − 8801 SA / JE

8. Use Methods

8.1. Overview of Functions

1) Clock functions

This function is used to set and read out month, day, hour, date, minute, second, and year (last two digits) data.

Any (two-digit) year that is a multiple of 4 is treated as a leap year and calculated automatically as such until the year

2099.

2) Fixed-cycle interrupt generation function

The fixed-cycle timer interrupt generation function generates an interrupt event periodically at any fixed cycle set between 244.14

μs and 4095 minutes.

When an interrupt event is generated, the /INT pin goes to low level ("L") and "1" is set to the TF bit to report that an event has occurred. (However, when a fixed-cycle timer interrupt event has been generated, low-level output from the

/INT pin occurs only when the value of the control register's TIE bit is "1". Up to 7.8 ms after the interrupt occurs, the

/INT status is automatically cleared (/INT status changes from low level to Hi-Z).

3) Time update interrupt function

The time update interrupt function generates interrupt events at one-second or one-minute intervals, according to the timing of the internal clock.

When an interrupt event occurs, the UF bit value becomes "1" and the /INT pin goes to low level to indicate that an event has occurred. (However, when a fixed-cycle timer interrupt event has been generated, low-level output from the

/INT pin occurs only when the value of the control register's UIE bit is "1". This /INT status is automatically cleared

(/INT status changes from low level to Hi-Z) 7.8

ms (a fixed value) after the interrupt occurs.

4) Alarm interrupt function

The alarm interrupt generation function generates interrupt events for alarm settings such as date, day, hour, and minute settings.

When an interrupt event occurs, the AF bit value is set to "1" and the /INT pin goes to low level to indicate that an event has occurred.

5) 32.768-kHz clock output

The 32.768-kHz clock (with precision equal to that of the built-in crystal oscillator) can be output via the FOUT pin.

The FOUT pin is a CMOS output pin which can be set for clock output when the FOE pin is at high level and for low-level output when the FOE pin is at high impedance.

6) Interface with CPU

Data is read and written via the I

2

C bus interface using two signal lines: SCL (clock) and SDA (data).

Since neither SCL nor SDA includes a protective diode on the V

DD side, a data interface between hosts with differing supply voltages can still be implemented by adding pull-up resistors to the circuit board.

The SCL's maximum clock frequency is 400 kHz (when V DD ≥ 1.8 V), which supports the I

2

C bus's high-speed mode.

Page - 6 ETM26E-03

RX − 8801 SA / JE

8.2. Description of Registers

8.2.1. Register table

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 Remark

0

1

2

SEC

MIN

HOUR

{

{

{

40

40

{

20

20

20

10

10

10

8

8

8

4

4

4

2

2

2

1

1

1

3

4

5

WEEK

DAY

MONTH

{

{

{

6

{

{

5

20

{

4

10

10

3

8

8

2

4

4

1

2

2

0

1

1

6

7

8

YEAR

RAM

MIN Alarm

80

AE

40

40

20

20

10

10

8

8

4

4

2

2

1

1

∗4

∗4 9

A

HOUR Alarm

WEEK Alarm

DAY Alarm

AE

AE

6

20

5

20

10

4

10

8

3

8

4

2

4

2

1

2

1

0

1

∗4

B

C

Timer Counter 0

Timer Counter 1

128

64

32

16

8

2048

4

1024

2

512

1

256

∗4

∗1, ∗3, ∗5 D Extension Register TEST WADA USEL TE FSEL1 FSEL0 TSEL1 TSEL0

E Flag Register

{ {

UF TF AF

{

VLF VDET ∗1, ∗2, ∗3

F Control Register CSEL1 CSEL0 UIE TIE AIE { { RESET ∗3

Note When after the initial power-up or when the result of read out the VLF bit is "1" , initialize all registers, before using the module.

Be sure to avoid entering incorrect date and time data, as clock operations are not guaranteed when the data or time data is incorrect.

∗1) During the initial power-up, the TEST bit is reset to "0" and the VLF bit is set to "1".

∗ At this point, all other register values are undefined, so be sure to perform a reset before using the module.

∗2) Only a "0" can be written to the UF, TF, AF, or VLF bit.

∗3) Any bit marked with "

{

" should be used with a value of "0" after initialization.

∗4) Any bit marked with " •" is a RAM bit that can be used to read or write any data.

∗5) The TEST bit is used by the manufacturer for testing. Be sure to set "0" for this bit when writing.

∗3

∗3

∗3

∗3

∗3

∗3

Page - 7 ETM26E-03

RX − 8801 SA / JE

8.2.2. Control register (Reg F)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

F

Control Register

(Default)

CSEL1

(0)

CSEL0

(1)

UIE

( −)

TIE

( −)

AIE

( −)

{

(0)

{

(0)

RESET

( −)

∗1) The default value is the value that is read (or is set internally) after powering up from 0 V.

∗2) "o" indicates write-protected bits. A zero is always read from these bits.

∗3) "−" indicates no default value has been defined.

• This register is used to control interrupt event output from the /INT pin and the stop/start status of clock and

calendar operations.

1) CSEL0,1 ( Compensation interval Select 0, 1 ) bits

The combination of these two bits is used to set the temperature compensation interval.

CSEL0,1

CSEL1

(bit 7)

CSEL0

(bit 6)

Compensation interval

Write/Read

0 1 2.0

1 0 10

1 1 30

2) UIE ( Update Interrupt Enable ) bit

When a time update interrupt event is generated (when the UF bit value changes from "0" to "1"), this bit's value specifies if an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated (/INT status remains Hi-Z).

When a "1" is written to this bit, an interrupt signal is generated (/INT status changes from Hi-Z to low) when an interrupt event is generated.

When a "0" is written to this bit, no interrupt signal is generated when an interrupt event occurs.

UIE Data Function

0

When a time update interrupt event occurs, an interrupt signal is not generated or is canceled (/INT status changes from low to Hi-Z).

Write/Read

1

When a time update interrupt event occurs, an interrupt signal is generated

(/INT status changes from Hi-Z to low).

When a time update interrupt event occurs, low-level output from the /INT pin occurs only when the value of the control register's UIE bit is "1". This /INT status is automatically cleared (/INT status changes from low to Hi-Z) 7.8

ms after the interrupt occurs.

2) TIE ( Timer Interrupt Enable ) bit

When a fixed-cycle timer interrupt event occurs (when the TF bit value changes from "0" to "1"), this bit's value specifies if an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated (/INT status remains Hi-Z).

When a "1" is written to this bit, an interrupt signal is generated (/INT status changes from Hi-Z to low) when an interrupt event is generated.

When a "0" is written to this bit, no interrupt signal is generated when an interrupt event occurs.

TIE Data Function

0

When a fixed-cycle timer interrupt event occurs, an interrupt signal is not generated or is canceled (/INT status changes from low to Hi-Z).

Write/Read

1

When a fixed-cycle timer interrupt event occurs, an interrupt signal is generated (/INT status changes from Hi-Z to low).

*

When a fixed-cycle timer interrupt event has been generated low-level output from the /INT pin occurs only when the value of the control register's TIE bit is "1". Up to 7.8 ms after the interrupt occurs, the /INT status is automatically cleared (/INT status changes from low to Hi-Z) .

Page - 8 ETM26E-03

RX − 8801 SA / JE

3) AIE ( Alarm Interrupt Enable ) bit

When an alarm timer interrupt event occurs (when the AF bit value changes from "0" to "1"), this bit's value specifies if an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated (/INT status remains Hi-Z).

When a "1" is written to this bit, an interrupt signal is generated (/INT status changes from Hi-Z to low) when an interrupt event is generated.

When a "0" is written to this bit, no interrupt signal is generated when an interrupt event occurs.

AIE Data Function

0

When an alarm interrupt event occurs, an interrupt signal is not generated or is canceled (/INT status changes from low to Hi-Z).

Write/Read

1

When an alarm interrupt event occurs, an interrupt signal is generated (/INT status changes from Hi-Z to low).

When an alarm interrupt event has been generated low-level output from the /INT pin occurs only when the value of the control register's AIE bit is "1". This setting is retained until the AF bit value is cleared to zero. (No automatic cancellation)

For details, see "8.5. Alarm Interrupt Function".

[Caution]

(1) The /INT pin is a shared interrupt output pin for three types of interrupts. It outputs the OR'ed result of these interrupt outputs.

When an interrupt has occurred (when the /INT pin is at low level), the UF, TF, read AF flags to determine which flag has a value of "1"

(this indicates which type of interrupt event has occurred).

(2) To keep the /INT pin from changing to low level, write "0" to the UIE, TIE, and AIE bits. To check whether an event has occurred without outputting any interrupts via the /INT pin, use software to monitor the value of the UF, TF, and AF interrupt flags.

4) RESET bit

It also resets the RTC module's internal counter value when the value is less than one second.

Writing a "1" to this bit stops the counter operation and resets the RTC module's internal counter value when the value is less than one second.

If a STOP-condition or repeated START-condition(I

2

C) is received while the 0.95-second bus timeout function is operating, stop status is automatically canceled (the RESET bit value is changed from "1" to "0").

∗ For optimum performance, do not use this bit for functions other than the clock and calendar functions.

RESET Data Description

Write/Read

0

1

[Normal operation mode]

This bit is used to cancel stop status for (i.e., restart) the clock and calendar function. Also, when "1" is written to the RESET bit, it cancels stop status for the fixed-cycle timer function.

Since operation is not restarted when the STOP bit value is "1", to restart operation, a "0" must be written to both the STOP bit and the RESET bit.

[Operation stop mode]

Stops updating of year, month, date, day, hour, minute, and second values and partially stops the fixed-cycle timer function.

(Stop 1) Stops updating of year, month, date, day, hour, minute, and second values

• This stops all clock and calendar update operations.

Once this occurs, no more time update interrupt events or alarm interrupt events occur.

(Stop 2) Partially stops the fixed-cycle timer function

• If the fixed-cycle timer's source clock settings include an update setting of 64 Hz, 1 Hz, or "Minute", the fixed-cycle timer function does not operate.

However, this function does operate when the fixed-cycle timer's source clock setting is

4096 Hz.

(Note) When this bit value is "1", the internal divider keeps the reset state, from 2048Hz to 1

Hz .

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8.2.3. Flag register (Reg-E)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

E

Flag register

(Default)

{

(0)

{

(0)

UF

( −)

TF

( −)

AF

( −)

{

(0)

VLF

(1)

VDET

(1)

∗1) The default value is the value that is read (or is set internally) after powering up from 0 V.

∗2) "o" indicates write-protected bits. A zero is always read from these bits.

∗3) "−" indicates a default value is undefined.

• This register is used to detect the occurrence of various interrupt events and reliability problems in internal data.

1) UF ( Update Flag ) bit

If set to "0" beforehand, this flag bit's value changes from "0" to 1" when a time update interrupt event has occurred. Once this flag bit's value is "1", its value is retained until a "0" is written to it.

For details, see "8.4. Time Update Interrupt Function".

2) TF ( Timer Flag ) bit

If set to "0" beforehand, this flag bit's value changes from "0" to 1" when a fixed-cycle timer interrupt event has occurred. Once this flag bit's value is "1", its value is retained until a "0" is written to it.

For details, see "8.3. Fixed-cycle Timer Interrupt Function".

3) AF ( Alarm Flag ) bit

If set to "0" beforehand, this flag bit's value changes from "0" to 1" when an alarm interrupt event has occurred.

Once this flag bit's value is "1", its value is retained until a "0" is written to it.

For details, see "8.5. Alarm Interrupt Function".

4) VLF ( Voltage Low Flag ) bit

This flag bit indicates the retained status of clock operations or internal data. Its value changes from "0" to "1" when data loss occurs, such as due to a supply voltage drop. Once this flag bit's value is "1", its value is retained until a "0" is written to it.

When after powering up from 0 V this bit's value is "1" .

VLF Data Description

0 The VLF bit is cleared to zero to prepare for the next status detection.

Write

1 This bit is invalid after a "1" has been written to it.

0

Data loss is not detected.

Read

1

Data loss is detected. All registers must be initialized.

( This setting is retained until a "zero" is written to this bit. )

5) VDET ( Voltage Detection Flag ) bit

This flag bit indicates the status of temperature compensation. Its value changes from "0" to "1" when stop the temperature compensation, such as due to a supply voltage drop. Once this flag bit's value is "1", its value is retained until a "0" is written to it.

When after powering up from 0 V this bit's value is "1" .

VDET Data Description

0 The VDET bit is cleared to zero to prepare for the next low voltage detection.

Write

1 The write access of "1" to this bit is invalid.

Read

0

1

Temperature compensation is normal.

Temperature compensation is stop detected.

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8.2.4. Extension register (Reg-D)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

D

Extension Register TEST WADA USEL

(Default) (0) ( −) ( −)

TE

( −)

FSEL1 FSEL0 TSEL1 TSEL0

(0) (0) ( −) ( −)

∗1) The default value is the value that is read (or is set internally) after powering up from 0 V.

∗2) "o" indicates write-protected bits. A zero is always read from these bits.

∗3) "−" indicates a default value is undefined.

• This register is used to specify the target for the alarm function or time update interrupt function and to select or set operations such as fixed-cycle timer operations.

1) TEST bit

This is the manufacturer's test bit. Its value should always be "0".

Be careful to avoid writing a "1" to this bit when writing to other bits.

If a "1" is inadvertently written to this TEST bit, there is a safety function where by this bit will be automatically cleared to zero when a STOP condition or Repeated START condition is received or when the 0.95-second bus timeout function operates.

TEST Data Description

0 Normal operation mode ∗ Default

Write/Read

1 Setting prohibited (manufacturer's test bit)

2) WADA ( Week Alarm/Day Alarm ) bit

This bit is used to specify either WEEK or DAY as the target of the alarm interrupt function.

Writing a "1" to this bit specifies DAY as the comparison object for the alarm interrupt function.

Writing a "0" to this bit specifies WEEK as the comparison object for the alarm interrupt function.

3) USEL ( Update Interrupt Select ) bit

This bit is used to specify either "second update" or "minute update" as the update generation timing of the time update interrupt function.

USEL

0 second update ∗ Default t RTN

500 ms

Write/Read

1 minute update 7.813 ms

4) TE ( Timer Enable ) bit

This bit controls the start/stop setting for the fixed-cycle timer interrupt function.

Writing a "1" to this bit specifies starting of the fixed-cycle timer interrupt function (a countdown starts from a preset value).

Writing a "0" to this bit specifies stopping of the fixed-cycle timer interrupt function.

5) FSEL0,1 ( FOUT frequency Select 0, 1 ) bits

The combination of these two bits is used to set the FOUT frequency.

FSEL0,1

FSEL1

(bit 3)

FSEL0

(bit 2)

FOUT frequency

0 0 Hz Output ∗ Default

Write/Read

0 1 Hz Output

1 0 Hz Output

1 1 Hz Output

6) TSEL0,1 ( Timer Select 0, 1 ) bits

The combination of these two bits is used to set the countdown period (source clock) for the fixed-cycle timer interrupt function (four settings can be made).

TSEL0,1

TSEL1

(bit 1)

TSEL0

(bit 0)

Source clock

0 0 4096 μs

Write/Read

0 1 64 Hz / Once per 15.625 ms

1

1

0

1

"Second" update /Once per second

"Minute" update /Once per minute

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8.2.5. RAM register (Reg - 7)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

7 RAM • • • • •

• This RAM register is read/write accessible for any data in the range from 00 h to FF h.

8.2.6. Clock counter (Reg - 0 ∼ 2)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3

• bit 2

• • bit 1 bit 0

0

1

2

SEC

MIN

HOUR

{

{

{

40

40

{

20

20

20

10

10

10

8

8

8

4

4

4

2

2

2

∗) "o" indicates write-protected bits. A zero is always read from these bits.

• The clock counter counts seconds, minutes, and hours.

• The data format is BCD format

.

For example, when the "seconds" register value is "0101 1001" it indicates 59 seconds.

∗ Note with caution that writing non-existent time data may interfere with normal operation of the clock counter.

1) Second counter

1

1

1

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

0 SEC { 40 20 10 8 4 2 1

• This second counter counts from "00" to "01," "02," and up to 59 seconds, after which it starts again from

00 seconds.

2) Minute counter

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

1 MIN { 40 20 10 8 4 2 1

• This minute counter counts from "00" to "01," "02," and up to 59 minutes, after which it starts again from

00 minutes.

3) Hour counter

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

2 HOUR

{ {

20 10 8 4 2 1

• This hour counter counts from "00" hours to "01," "02," and up to 23 hours, after which it starts again from

00 hours.

8.2.7. Day counter (Reg - 3) bit 0 Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1

3 WEEK

{

6 5 4 3 2 1

∗) "o" indicates write-protected bits. A zero is always read from these bits.

• The day (of the week) is indicated by 7 bits, bit 0 to bit 6.

The day data values are counted as: Day 01h → Day 02h → Day 04h → Day 08h → Day 10h → Day

20h → Day 40h → Day 01h → Day 02h, etc.

• The correspondence between days and count values is shown below.

WEEK bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 Day

0

Data [h]

Write/Read

Write prohibit

0 0 0 0 0 0 0 1

0 0 0 0 0 0 1

0 0 0 0 0 1

0 0 0 0 1 0 0 0 Wednesday

0 0 0 1

0 0 1

0 1

∗ Do not set "1" to more than one day at the same time.

Also, note with caution that any setting other than the seven shown above should not be made as it may interfere with normal operation.

− −

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8.2.8. Calendar counter (Reg 4 to 6)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

4

5

DAY

MONTH

{

{

{

{

20

{

10

10

8

8

4

4

2

2

1

1

6 YEAR 80 40 20 10 8 4 2 1

∗) "o" indicates write-protected bits. A zero is always read from these bits.

• The auto calendar function updates all dates, months, and years from January 1, 2001 to December 31, 2099.

• The data format is BCD format. For example, a date register value of "0011 0001" indicates the 31st.

∗ Note with caution that writing non-existent date data may interfere with normal operation of the calendar counter.

1) Date counter

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

4 DAY

{ {

20 10 8 4 2

• The updating of dates by the date counter varies according to the month setting.

∗ A leap year is set whenever the year value is a multiple of four (such as 04, 08, 12, 88, 92, or 96). In

February of a leap year, the counter counts dates from "01," "02," "03," to "28," "29," "01," etc.

DAY Month Date update pattern

1

Write/Read

1, 3, 5, 7, 8, 10, or 12

4, 6, 9, or 11

February in normal year

February in leap year

01, 02, 03 ∼ 30, 31, 01 ∼

01, 02, 03 ∼ 30, 01, 02 ∼

01, 02, 03 ∼ 28, 01, 02 ∼

01, 02, 03 ∼ 28, 29, 01 ∼

2) Month counter

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

5 MONTH { { { 10 8 4 2 1

• The month counter counts from 01 (January), 02 (February), and up to 12 (December), then starts again at

01 (January).

3) Year counter

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

Y1 6 Years Y80 Y40 Y20 Y10 Y8 Y4

• The year counter counts from 00, 01, 02 and up to 99, then starts again at 00.

• Any year that is a multiple of four (04, 08, 12, 88, 92, 96, etc.) is handled as a leap year.

8.2.9. Alarm registers (Reg - 8 ∼ A)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2

Y2 bit 1 bit 0

8

9

A

MIN Alarm

HOUR Alarm

WEEK Alarm

DAY Alarm

AE

AE

AE

40

6

20

20

5

20

10

10

4

10

8

8

3

8

4

4

2

4

2

2

1

2

1

1

0

1

• The alarm interrupt function is used, along with the AEI, AF, and WADA bits, to set alarms for specified date, day, hour, and minute values.

• When the settings in the above alarm registers and the WADA bit match the current time, the /INT pin goes to low level and "1" is set to the AF bit to report that and alarm interrupt event has occurred.

8.2.10. Fixed-cycle timer control registers (Reg - B to C)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

B

C

Timer Counter 0

Timer Counter 1

128

64

32

16

8

2048

4

1024

2

512

1

256

• These registers are used to set the preset countdown value for the fixed-cycle timer interrupt function.

The TE, TF, TIE, and TSEL0/1 bits are also used to set the fixed-cycle timer interrupt function.

• When the value in the above fixed-cycle timer control register changes from 001h to 000h, the /INT pin goes to low level and "1" is set to the TF bit to report that a fixed-cycle timer interrupt event has occurred.

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8.3. Fixed-cycle Timer Interrupt Function

The fixed-cycle timer interrupt generation function generates an interrupt event periodically at any fixed cycle set between 244.14

μs and 4095 minutes.

When an interrupt event is generated, the /INT pin goes to low level and "1" is set to the TF bit to report that an event has occurred. (However, when a fixed-cycle timer interrupt event has been generated low-level output from the /INT pin occurs only when the value of the control register's TIE bit is "1". Up to 7.8 ms after the interrupt occurs, the /INT status is automatically cleared (/INT status changes from low-level to Hi-Z).

Example of

/INT operation

7.8ms

(Max.) period TIE = " 1 " → " 0 " TIE = " 1 "

TE = " 0 " → " 1 "

8.3.1. Diagram of fixed-cycle timer interrupt function

Fixed-cycle timer starts Fixed-cycle timer stops

TE bit

(1)

Operation of fixed-cycle timer

(7)

" 1 "

" 0 "

" 1 " (9)

TIE bit

(5)

" 1 "

" 0 "

/INT output

TF bit

Event occurs

(6) tRTN

(1)

(4)

(3) period

• • •

001 h → 000 h

(2) period tRTN

(8)

∗ Even when the TF bit is cleared to zero, the /INT status does not change. period tRTN period

∗ When the TE bit value changes from "0" to "1" the fixed-cycle timer function starts.

The counter always starts counting down from the preset value when the TE value changes from "0" to "1".

(7) tRTN

∗ Even when the TE bit is cleared to zero, /INT remains low during the tRTN time.

Hi - z

" L "

" 1 "

" 0 "

(7)

RTC internal operation

Write operation

(1) When a "1" is written to the TE bit, the fixed-cycle timer countdown starts from the preset value.

(2) A fixed-cycle timer interrupt event starts a countdown based on the countdown period (source clock). When the count value changes from 001h to 000h, an interrupt event occurs.

∗ After the interrupt event that occurs when the count value changes from 001h to 000h, the counter automatically reloads the preset value and again starts to count down. (Repeated operation)

(3) When a fixed-cycle timer interrupt event occurs, "1" is written to the TF bit.

(4) When the TF bit = "1" its value is retained until it is cleared to zero.

(5) If the TIE bit = "1" when a fixed-cycle timer interrupt occurs, /INT pin output goes low.

∗ If the TIE bit = "0" when a fixed-cycle timer interrupt occurs, /INT pin output remains Hi-Z.

(6) Output from the /INT pin remains low during the tRTN period following each event, after which it is automatically cleared to Hi-Z status.

∗ /INT is again set low when the next interrupt event occurs.

(7) When a "0" is written to the TE bit, the fixed-cycle timer function is stopped and the /INT pin is set to Hi-Z status.

∗ When /INT = low, the fixed-cycle timer function is stopped. The tRTN period is the maximum amount of time before the /INT pin status changes from low to Hi-Z.

(8) As long as /INT = low, the /INT pin status does not change when the TF bit value changes from "1" to "0".

(9) When /INT = low, the /INT pin status changes from low to Hi-Z as soon as the TIE bit value changes from "1" to

"0".

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8.3.2. Related registers for function of time update interrupts.

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

B

C

D

E

F

Timer Counter 0

Timer Counter 1

Extension Register

Flag Register

Control Register

128

TEST

{

CSEL1

64

{

WADA

CSEL0

32

USEL

UF

UIE

16

TE

TF

TIE

8

2048

FSEL1

AF

AIE

4

1024

FSEL0

{

{

2

512

1

256

TSEL1 TSEL0

VLF

{

VDET

RESET

∗1) "o" indicates write-protected bits. A zero is always read from these bits.

∗2) Bits marked with "•" are RAM bits that can contain any value and are read/write-accessible.

∗ Before entering settings for operations, we recommend writing a "0" to the TE and TIE bits to prevent hardware interrupts from occurring inadvertently while entering settings.

∗ When the STOP bit or RESET bit value is "1" the time update interrupt function operates only partially.

(Operation continues if the source clock setting is 4096 Hz. Otherwise, operation is stopped.)

∗ When the fixed-cycle timer interrupt function is not being used, the fixed-cycle timer control register (Reg – B to C) can be used as a RAM register. In such cases, stop the fixed-cycle timer function by writing "0" to the TE and TIE bits.

1) TSEL0,1 bits (Timer Select 0, 1)

The combination of these two bits is used to set the countdown period (source clock) for the fixed-cycle timer interrupt function (four settings can be made).

TSEL0,1

TSEL1

(bit 1)

TSEL0

(bit 0)

Source clock

Auto reset time tRTN

Effects of

RESET bits

Write/Read

0 0

0 1

1

1

0

1

4096 μ

"Second" update /Once per second s

Once per 15.625

ms

"Minute" update /Once per minute

122 μs

7.8125

ms

Does not operate when the RESET bit value is "1".

∗1) The /INT pin's auto reset time (tRTN) varies as shown above according to the source clock setting.

∗2) When the source clock has been set to "second update" or "minute update", the timing of both countdown and interrupts is coordinated with the clock update timing.

7.8125

ms

7.8125

ms

2) Fixed-cycle Timer Control register (Reg - B to C)

This register is used to set the default (preset) value for the counter. Any count value from 1 (001 h) to

4095 (FFFh) can be set. The counter counts down based on the source clock's period, and when the count value changes from 001h to 000h, the TF bit value becomes "1".

The countdown that starts when the TE bit value changes from "0" to "1" always begins from the preset value.

Be sure to write "0" to the TE bit before writing the preset value. If a value is written while TE = "1" the first subsequent event will not be generated correctly.

Address C

Timer Counter 1

Address B

Timer Counter 0 bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

• •

3) TE (Timer Enable) bit

• • 2048 1024 512 256 128 64 32 16 8 4 2 1

This bit controls the start/stop setting for the fixed-cycle timer interrupt function.

TE Data Description

0 Stops fixed-cycle timer interrupt function.

Write/Read

1

Starts fixed-cycle timer interrupt function.

The countdown that starts when the TE bit value changes from "0" to "1" always begins from the preset value.

4) TF (Timer Flag) bit

If set to "0" beforehand, this flag bit's value changes from "0" to 1" when a fixed-cycle timer interrupt event has occurred. Once this flag bit's value is "1", its value is retained until a "0" is written to it.

TF Data Description

Write

0

The TF bit is cleared to zero to prepare for the next status detection

∗ Clearing this bit to zero does not enable the /INT low output status to be cleared (to Hi-Z).

1 This bit is invalid after a "1" has been written to it.

0

Read

1

Fixed-cycle timer interrupt events are not detected.

Fixed-cycle timer interrupt events are detected.

(Result is retained until this bit is cleared to zero.)

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5) TIE (Timer Interrupt Enable) bit

When a fixed-cycle timer interrupt event occurs (when the TF bit value changes from "0" to "1"), this bit's value specifies whether an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated (/INT status remains Hi-Z).

TIE Data Description

0

1) When a fixed-cycle timer interrupt event occurs, an interrupt signal is not generated or is canceled (/INT status remains Hi-Z).

2) When a fixed-cycle timer interrupt event occurs, the interrupt signal is canceled (/INT status changes from low to Hi-Z).

Even when the TIE bit value is "0" another interrupt event may change the /INT status to low (or may hold /INT = "L"). Write/Read

1

When a fixed-cycle timer interrupt event occurs, an interrupt signal is generated (/INT status changes from Hi-Z to low).

When a fixed-cycle timer interrupt event has been generated low-level output from the /INT pin occurs only when the value of the control register's TIE bit is "1". Up to 7.8 ms after the interrupt occurs, the /INT status is automatically cleared (/INT status changes from low to Hi-Z).

8.3.3. Fixed-cycle timer interrupt interval (example)

Timer

Counter setting

0

1

2

41

205

410

2048

4096 Hz

TSEL1,0 = 0,0

244.14 μ s

488.28 μ s

10.010 ms

50.049 ms

100.10 ms

500.00 ms

Source clock

64 Hz

TSEL1,0 = 0,1

15.625 ms

31.25 ms

"Second" update

TSEL1,0 = 1,0

1 s

2 s

640.63 ms

3.203 s

6.406 s

32.000 s

41 s

205 s

410 s

2048 s

"Minute" update

TSEL1,0 = 1,1

1 min

2 min

41 min

205 min

410 min

2048 min

4095 0.9998 s 63.984 s 4095 s 4095 min

• Time error in fixed-cycle timer

A time error in the fixed-cycle timer will produce a positive or negative time period error in the selected source clock. The fixed-cycle timer's time is within the following range relative to the time setting.

(Fixed-cycle timer's time setting ( ∗) − source clock period) to (timer's time setting)

∗ ) The timer's time setting = source clock period × timer counter's division value.

∗ The time actually set to the timer is adjusted by adding the time described above to the communication time for the serial data transfer clock used for the setting.

8.3.4. Fixed-cycle timer start timing

Counting down of the fixed-cycle timer value starts at the rising edge of the SCL signal that occurs when the TE value is changed from "0" to "1" (after bit 0 is transferred).

Address D

SCL pin

TE FSEL1 FSEL0 TSEL1 TSEL0 ACK SDA pin

Internal timer

/INT pin

Operation of timer

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8.4. Time Update Interrupt Function

The time update interrupt function generates interrupt events at one-second or one-minute intervals, according to the timing of the internal clock.

When an interrupt event occurs, the UF bit value becomes "1" and the /INT pin goes to low level to indicate that an event has occurred. (However, when a fixed-cycle timer interrupt event has been generated, low-level output from the /INT pin occurs only when the value of the control register's UIE bit is "1". This /INT status is automatically cleared (/INT status changes from low level to Hi-Z) 7.8

ms (fixed value) after the interrupt occurs.

/INT operation example

UIE = " 1 "

8.4.1. Time update interrupt function diagram

7.8ms

period UIE = " 1 " → " 0 "

" 1 " (7)

UIE bit

(4)

" 1 "

" 0 "

/INT output

UF bit

(5) tRTN period

(2)

(1)

(3) period tRTN

(6)

∗ /INT status does not change when UF bit is cleared to zero. period tRTN period tRTN

Hi - z

" L "

" 1 "

" 0 "

Events

Operation in RTC i ' i

Write operation

(1) A time update interrupt event occurs when the internal clock's value matches either the second update time or the minute update time. The USEL bit's specification determines whether it is the second update time or the minute update time that must be matched.

(2) When a time update interrupt event occurs, the UF bit value becomes "1".

(3) When the UF bit value is "1" its value is retained until it is cleared to zero.

(4) When a time update interrupt occurs, /INT pin output is low if UIE = "1".

∗ If UIE = "0" when a timer update interrupt occurs, the /INT pin status remains Hi-Z.

(5) Each time an event occurs, /INT pin output is low only up to the tRTN time (which is fixed as 7.1825 ms for time update interrupts) after which it is automatically cleared to Hi-Z.

∗ /INT pin output goes low again when the next interrupt event occurs.

(6) As long as /INT = low, the /INT pin status does not change, even if the UF bit value changes from "1" to "0".

(7) When /INT = low, the /INT pin status changes from low to Hi-Z as soon as the UIE bit value changes from "1" to "0".

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8.4.2. Related registers for time update interrupt functions.

Address Function bit 7 bit 6 bit 5

D

E

F

Extension Register

Flag Register

Control Register

TEST

{

CSEL1

WADA

{

CSEL0

∗) "o" indicates write-protected bits. A zero is always read from these bits.

USEL

UF

UIE bit 4

TE

TF

TIE bit 3

FSEL1

AF

AIE bit 2

FSEL0

{

{ bit 1

TSEL1

VLF

{ bit 0

TSEL0

VDET

RESET

∗ Before entering settings for operations, we recommend writing a "0" to the UIE bit to prevent hardware interrupts from occurring inadvertently while entering settings.

∗ When the RESET bit value is "1" time update interrupt events do not occur.

∗ Although the time update interrupt function cannot be fully stopped, if "0" is written to the UIE bit, the time update interrupt function can be prevented from changing the /INT pin status to low.

1) USEL (Update Interrupt Select) bit

This bit is used to select "second" update or "minute" update as the timing for generation of time update interrupt events.

USEL Data Description

0

Selects "second update" (once per second) as the timing for generation of interrupt events

Write/Read

1

Selects "minute update" (once per minute) as the timing for generation of interrupt events

2) UF (Update Flag) bit

Once it has been set to "0", this flag bit value changes from "0" to "1" when a time update interrupt event occurs.

When this flag bit = "1" its value is retained until a "0" is written to it.

UF Data Description

Write

0

1

The UF bit is cleared to zero to prepare for the next status detection

Clearing this bit to zero does not enable the /INT low output status to be cleared (to Hi-Z).

This bit is invalid after a "1" has been written to it.

0

Read

1

Time update interrupt events are not detected.

Time update interrupt events are detected.

(The result is retained until this bit is cleared to zero.)

3) UIE (Update Interrupt Enable) bit

When a time update interrupt event occurs (UF bit value changes from "0" to "1"), this bit selects whether to generate an interrupt signal (/INT status changes from Hi-Z to low) or to not generate it (/INT status remains

Hi-Z).

UIE Data Description

Write/Read

0

1

1) Does not generate an interrupt signal when a time update interrupt event occurs (/INT remains Hi-Z)

2) Cancels interrupt signal triggered by time update interrupt event (/INT changes from low to Hi-Z).

Even when the UIE bit value is "0" another interrupt event may change the /INT status to low (or may hold /INT = "L").

When a time update interrupt event occurs, an interrupt signal is generated

(/INT status changes from Hi-Z to low).

When a time update interrupt event occurs, low-level output from the /INT pin occurs only when the UIE bit value is "1". Up to 7.8

ms after the interrupt occurs, the /INT status is automatically cleared (/INT status changes from low to Hi-Z).

Page - 18 ETM26E-03

RX − 8801 SA / JE

8.5. Alarm Interrupt Function

The alarm interrupt generation function generates interrupt events for alarm settings such as date, day, hour, and minute settings.

When an interrupt event occurs, the AF bit value is set to "1" and the /INT pin goes to low level to indicate that an event has occurred.

Example of

/INT operation

AIE = " 1 " ( AF = " 0 " → " 1 " ) AF = " 1 " → " 0 " or

AIE = " 1 " → " 0 "

8.4.1. Diagram of alarm interrupt function

" 1 "

AIE bit

(4)

" 1 "

" 0 "

(5)

/INT output

(7)

Hi - z

" L "

(6)

AF bit (2)

(3)

" 1 "

" 0 "

(1)

Event occurs

RTC internal operation

Write operation

(1) The hour, minute, date or day when an alarm interrupt event is to occur is set in advance along with the WADA bit, and when the setting matches the current time an interrupt event occurs.

(Note) Even if the current date/time is used as the setting, the alarm will not occur until the counter counts up to the current date/time (i.e., an alarm will occur next time, not immediately).

(2) When a time update interrupt event occurs, the AF bit values becomes "1".

(3) When the AF bit = "1", its value is retained until it is cleared to zero.

(4) If AIE = "1" when an alarm interrupt occurs, the /INT pin output goes low.

∗ When an alarm interrupt event occurs, /INT pin output goes low, and this status is then held until it is cleared via the AF bit or AIE bit.

(5) If the AIE value is changed from "1" to "0" while /INT is low, the /INT status immediately changes from low to

Hi-Z. After the alarm interrupt occurs and before the AF bit value is cleared to zero, the /INT status can be controlled via the AIE bit.

(6) If the AF bit value is changed from "1" to "0" while /INT is low, the /INT status immediately changes from low to

Hi-Z.

(7) If the AIE bit value is "0" when an alarm interrupt occurs, the /INT pin status remains Hi-Z.

Page - 19 ETM26E-03

RX − 8801 SA / JE

8.5.2. Related registers

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

1

2

3

4

8

9

MIN

HOUR

WEEK

DAY

MIN Alarm

{

{

{

{

40

{

6

{

20

20

5

20

20

10

10

4

10

10

8

8

3

8

8

4

4

2

4

4

2

2

1

2

2

1

1

0

1

1

A

HOUR Alarm

WEEK Alarm

DAY Alarm

AE

AE

AE

40

6

20

5

20

10

4

10

8

3

8

4

2

4

2

1

2

1

0

1

D

E

F

Extension Register

Flag Register

Control Register

TEST

{

CSEL1

WADA

{

CSEL0

USEL

UF

UIE

TE

TF

TIE

FSEL1

AF

AIE

FSEL0

{

{

TSEL1

VLF

{

TSEL0

VDET

RESET

∗1) "o" indicates write-protected bits. A zero is always read from these bits.

∗2) Bits marked with "•" are RAM bits that can contain any value and are read/write-accessible.

∗ Before entering settings for operations, we recommend writing a "0" to the AIE bit to prevent hardware interrupts from occurring inadvertently while entering settings.

∗ When the RESET bit value is "1" alarm interrupt events do not occur.

∗ When the alarm interrupt function is not being used, the Alarm registers (Reg - 8 to A) can be used as a RAM register. In such cases, be sure to write "0" to the AIE bit.

∗ When the AIE bit value is "1" and the Alarm registers (Reg - 8 to A) is being used as a RAM register, /INT may be changed to low level unintentionally.

1) WADA (Week Alarm /Day Alarm) bit

The alarm interrupt function uses either "Day" or "Week" as its target. The WADA bit is used to specify either

WEEK or DAY as the target for alarm interrupt events.

WADA Data Description

0

Sets WEEK as target of alarm function

(DAY setting is ignored)

Write/Read

1

Sets DAY as target of alarm function

(WEEK setting is ignored)

2) Alarm registers (Reg - 8 to A)

Address Function bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

8

9

A

MIN Alarm

HOUR Alarm

WEEK Alarm

DAY Alarm

AE

AE

AE

40

6

20

20

5

20

10

10

4

10

8

8

3

8

4

4

2

4

2

2

1

2

1

1

0

1

The hour, minute, date or day when an alarm interrupt event will occur is set using this register and the

WADA bit.

In the WEEK alarm /Day alarm register (Reg - A), the setting selected via the WADA bit determines whether

WEEK alarm data or DAY alarm data will be set. If WEEK has been selected via the WADA bit, multiple days can be set (such as Monday, Wednesday, Friday, Saturday).

When the settings made in the alarm registers and the WADA bit match the current time, the AF bit value is changed to "1". At that time, if the AIE bit value has already been set to "1", the /INT pin goes low.

∗1) The register that "1" was set to "AE" bit, doesn't compare alarm.

(Example) Write 80h (AE = "1") to the WEEK Alarm /DAY Alarm register (Reg - A):

Only the hour and minute settings are used as alarm comparison targets. The week and date settings are not used as alarm comparison targets.

As a result, alarm occurs if only an hour and minute accords with alarm data.

∗2) If all three AE bit values are "1" the week/date settings are ignored and an alarm interrupt event will occur once per minute.

Page - 20 ETM26E-03

RX − 8801 SA / JE

3) AF (Alarm Flag) bit

When this flag bit value is already set to "0", occurrence of an alarm interrupt event changes it to "1". When this flag bit value is "1", its value is retained until a "0" is written to it.

AF Data Description

Write

0

The AF bit is cleared to zero to prepare for the next status detection

Clearing this bit to zero enables /INT low output to be canceled (/INT remains Hi-Z) when an alarm interrupt event has occurred.

1 This bit is invalid after a "1" has been written to it.

0 Alarm interrupt events are not detected.

Read

1

Alarm interrupt events are detected.

(Result is retained until this bit is cleared to zero.)

4) AIE (Alarm Interrupt Enable) bit

When an alarm interrupt event occurs (when the AF bit value changes from "0" to "1"), this bit's value specifies whether an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated (/INT status remains Hi-Z).

AIE Data Description

Write/Read

0

1) When an alarm interrupt event occurs, an interrupt signal is not generated or is canceled (/INT status remains Hi-Z).

2) When an alarm interrupt event occurs, the interrupt signal is canceled

(/INT status changes from low to Hi-Z).

Even when the AIE bit value is "0" another interrupt event may change the /INT status to low

(or may hold /INT = "L").

1

When an alarm interrupt event occurs, an interrupt signal is generated (/INT status changes from Hi-Z to low).

When an alarm interrupt event occurs, low-level output from the /INT pin occurs only when the

AIE bit value is "1". This value is retained (not automatically cleared) until the AF bit is cleared to zero.

8.5.2. Examples of alarm settings

1) Example of alarm settings when "Day" has been specified (and WADA bit = "0")

Reg – A

Day is specified

WADA bit = "0" bit

7

AE bit

6

S bit

5

F bit

4

T bit

3

W bit

2

T bit

1

M bit

0

S

Reg - 9

HOUR

Alarm

Reg - 8

MIN

Alarm

Monday through Friday, at 7:00 AM

∗ Minute value is ignored

0 1 1 1 1 1 0 07 h

Every Saturday and Sunday, for 30 minutes each hour ∗ Hour value is ignored

0 1 0 0 0 0 0 1

Every day, at 6:59 AM

0 1 1 1 1 1 1 1

1 Χ Χ Χ Χ Χ Χ Χ

Χ: Don't care

2) Example of alarm settings when "Day" has been specified (and WADA bit = "1")

80 h ∼ FF h

18 h

Reg - 9

Day is specified

WADA bit = "1" bit

7

AE bit

6

• bit

5

20

Reg - A bit

4

10 bit

3

08 bit

2

04 bit

1

02 bit

0

01

HOUR

Alarm

First of each month, at 7:00 AM

∗ Minute value is ignored

15 th

of each month, for 30 minutes each hour ∗ Hour value is ignored

0

0

0

0

0

0

0

0

1

0

0

0

1

0

0

1

1

07 h

80 h ∼ FF h

80 h ∼ FF h

30 h

59 h

Reg - 8

MIN

Alarm

80 h ∼ FF h

30 h

Every day, at 6:59 PM

Χ: Don't care

1 Χ Χ Χ Χ Χ Χ Χ 18 h 59 h

Page - 21 ETM26E-03

RX − 8801 SA / JE

8.6. Reading/Writing Data via the I 2 C Bus Interface

8.6.1. Overview of I 2 C-BUS

The I

2

C bus supports bi-directional communications via two signal lines: the SDA (data) line and SCL (clock) line. A combination of these two signals is used to transmit and receive communication start/stop signals, data transfer signals, acknowledge signals, and so on.

Both the SCL and SDA signals are held at high level whenever communications are not being performed.

The starting and stopping of communications is controlled at the rising edge or falling edge of SDA while SCL is at high level.

During data transfers, data changes that occur on the SDA line are performed while the SCL line is at low level, and on the receiving side the data is output while the SCL line is at high level.

The I

2

C bus device does not include a chip select pin such as is found in ordinary logic devices. Instead of using a chip select pin, slave addresses are allocated to each device and the receiving device responds to communications only when its slave address matches the slave address in the received data. In either case, the data is transferred via the SCL line at a rate of one bit per clock pulse.

8.6.2. System configuration

All ports connected to the I 2 C bus must be either open drain or open collector ports in order to enable AND connections to multiple devices.

SCL and SDA are both connected to the V

DD

line via a pull-up resistance. Consequently, SCL and SDA are both held at high level when the bus is released (when communication is not being performed).

V DD

SDA

SCL

Master

Transmitter/

Receiver

Slave

Transmitter/

Receiver

Master

Transmitter/

Receiver

Slave

Transmitter/

Receiver

CPU, etc. RX - 8801

Other I

2

C bus device

Any device that controls the data transmission and data reception is defined as a "Master".

and any device that is controlled by a master device is defined as a “Slave”.

The device transmitting data is defined as a “Transmitter” and the device receiving data is defined as a receiver”

In the case of this RTC module, controllers such as a CPU are defined as master devices and the RTC module is defined as a slave device. When a device is used for both transmitting and receiving data, it is defined as either a transmitter or receiver depending on these conditions.

Page - 22 ETM26E-03

RX − 8801 SA / JE

8.6.3. Starting and stopping I

2

C bus communications

START condition

Repeated START(RESTART) condition

SCL

[ S ] [ Sr ]

SDA

STOP condition

[ P ]

0.95

s ( Max. )

1) START condition, repeated START condition, and STOP condition

(1) START condition

The SDA level changes from high to low while SCL is at high level.

(2) STOP condition

• This condition regulates how communications on the I2C-BUS are terminated.

The SDA level changes from low to high while SCL is at high level.

(3) Repeated START condition (RESTART condition)

• In some cases, the START condition occurs between a previous START condition and the next

STOP condition, in which case the second START condition is distinguished as a RESTART condition. Since the required status is the same as for the START condition, the SDA level changes from high to low while SCL is at high level.

2) Caution points

∗1) The master device always controls the START, RESTART, and STOP conditions for communications.

∗2) The master device does not impose any restrictions on the timing by which STOP conditions affect transmissions, so communications can be forcibly stopped at any time while in progress. (However, this is only when this RTC module is in receiver mode (data reception mode = SDA released).

∗3) When communicating with this RTC module, the series of operations from transmitting the START condition to transmitting the STOP condition should occur within 0.95 seconds. (A RESTART condition may be sent between a START condition and STOP condition, but even in such cases the series of operations from transmitting the START condition to transmitting the STOP condition should still occur within 0.95 seconds.)

If this series of operations requires 0.95 seconds or longer, the I

2

C bus interface will be automatically cleared and set to standby mode by this RTC module's bus timeout function. Note with caution that both write and read operations are invalid for communications that occur during or after this auto clearing operation. (When the read operation is invalid, all data that is read has a value of "1").

Restarting of communications begins with transfer of the START condition again

∗4) When communicating with this RTC module, wait at least 1.3 μs (see the tBUF rule) between transferring a STOP condition (to stop communications) and transferring the next START condition (to start the next round of communications).

STOP condition

START condition

SCL

[ P ] [ S ]

SDA

61 μs (Min.)

Page - 23 ETM26E-03

RX − 8801 SA / JE

8.6.4. Data transfers and acknowledge responses during I 2 C-BUS communications

1) Data transfers

Data transfers are performed in 8-bit (1 byte) units once the START condition has occurred. There is no limit on the amount (bytes) of data that are transferred between the START condition and STOP condition.

(However, the transfer time must be no longer than 0.95 seconds.)

The address auto increment function operates during both write and read operations.

After address Fh, incrementation goes to address 0h .

Updating of data on the transmitter (transmitting side)'s SDA line is performed while the SCL line is at low level.

The receiver (receiving side) receives data while the SCL line is at high level.

SCL

SDA

Data is valid when data line is stable

Data can be changed

∗ Note with caution that if the SDA data is changed while the SCL line is at high level, it will be treated as a

START, RESTART, or STOP condition.

2) Data acknowledge response (ACK signal)

When transferring data, the receiver generates a confirmation response (ACK signal, low active) each time an

8-bit data segment is received. If there is no ACK signal from the receiver, it indicates that normal communication has not been established. (This does not include instances where the master device intentionally does not generate an ACK signal.)

Immediately after the falling edge of the clock pulse corresponding to the 8th bit of data on the SCL line, the transmitter releases the SDA line and the receiver sets the SDA line to low (= acknowledge) level.

SCL from Master

1 2 8 9

SDA from transmitter

(sending side)

Release SDA

SDA from receiver

(receiving side)

Low active

ACK signal

After transmitting the ACK signal, if the Master remains the receiver for transfer of the next byte, the SDA is released at the falling edge of the clock corresponding to the 9th bit of data on the SCL line. Data transfer resumes when the Master becomes the transmitter.

When the Master is the receiver, if the Master does not send an ACK signal in response to the last byte sent from the slave, that indicates to the transmitter that data transfer has ended. At that point, the transmitter continues to release the SDA and awaits a STOP condition from the Master.

8.6.5. Slave address

The I 2 C bus device does not include a chip select pin such as is found in ordinary logic devices. Instead of using a chip select pin, slave addresses are allocated to each device.

All communications begin with transmitting the [START condition] + [slave address (+ R/W specification)]. The receiving device responds to this communication only when the specified slave address it has received matches its own slave address.

Slave addresses have a fixed length of 7 bits. This RTC's slave address is [0110 010].

An R/W bit ("*" above) is added to each 7-bit slave address during 8-bit transfers.

Slave address R/W bit

Transfer data bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0

Read

Write

65 h

64 h

0 1 1 0 0 1 0

1 (= Read)

0 (= Write)

Page - 24 ETM26E-03

RX − 8801 SA / JE

8.6.6. I 2 C bus protocol

In the following sequence descriptions, it is assumed that the CPU is the master and the RX-8801 is the slave. a. Address specification write sequence

Since the RX-8801 includes an address auto increment function, once the initial address has been specified, the

RX-8801 increments (by one byte) the receive address each time data is transferred.

(1) CPU transfers start condition [S].

(2) CPU transmits the RX-8801's slave address with the R/W bit set to write mode.

(3) Check for ACK signal from RX-8801.

(4) CPU transmits write address to RX-8801.

(5) Check for ACK signal from RX-8801.

(6) CPU transfers write data to the address specified at (4) above.

(7) Check for ACK signal from RX-8801.

(8) Repeat (6) and (7) if necessary. Addresses are automatically incremented.

(9) CPU transfers stop condition [P].

(1) (2) (3) (4) (5) (6) (7) (8) (9)

S Slave address 0

R/W

0 Address 0 Data 0 Data 0 P

ACK signal from RX-8801 b. Address specification read sequence

After using write mode to write the address to be read, set read mode to read the actual data.

(1) CPU transfers start condition [S].

(2) CPU transmits the RX-8801's slave address with the R/W bit set to write mode.

(3) Check for ACK signal from RX-8801.

(4) CPU transfers address for reading from 8801.

(5) Check for ACK signal from RX-8801.

(6) CPU transfers RESTART condition [Sr] (in which case, CPU does not transfer a STOP condition [P]).

(7) CPU transfers RX-8801's slave address with the R/W bit set to read mode.

(8) Check for ACK signal from RX-8801 (from this point on, the CPU is the receiver and the RX-8801 is the transmitter).

(9) Data from address specified at (4) above is output by the RX-8801.

(10) CPU transfers ACK signal to RX-8801.

(11) Repeat (9) and (10) if necessary. Read addresses are automatically incremented.

(12) CPU transfers ACK signal for "1".

(13) CPU transfers stop condition [P].

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13)

S Slave address 0

R/W

0 Address 0 Sr Slave address 1

R/W

0 Data 0 Data 1 P

ACK from RX-8801 ACK from CPU c. Read sequence when address is not specified

Once read mode has been initially set, data can be read immediately. In such cases, the address for each read operation is the previously accessed address + 1.

(1) CPU transfers start condition [S].

(2) CPU transmits the RX-8801's slave address with the R/W bit set to read mode.

(3) Check for ACK signal from RX-8801 (from this point on, the CPU is the receiver and the RX-8801 is the transmitter).

(4) Data is output from the RX-8801 to the address following the end of the previously accessed address.

(5) CPU transfers ACK signal to RX-8801.

(6) Repeat (4) and (5) if necessary. Read addresses are automatically incremented in the RX-8801.

(7) CPU transfers ACK signal for "1".

(8) CPU transfers stop condition [P].

(1) (2) (3) (4) (5) (6) (7) (8)

S Slave address 0 Data 1 P 1

R/W

0

ACK from RX-8801

Data

ACK from CPU

Page - 25 ETM26E-03

RX − 8801 SA / JE

8.7. Backup and Recovery

V DD

V CLK

0 V t

R1 t

F

Back up

Item

Power supply detection voltage ( 1 )

Power supply detection voltage ( 2 )

Power supply drop time

Initial power-up time

Clock maintenance power-up time

Symbol

V

DET

V

LOW t F t

R1 t

R2

Condition

1.6V → V DD ≤ 3.6V

1.6V → V DD > 3.6V t

R2

Min.

V DET

Typ. Max. Unit.

Page - 26 ETM26E-03

RX − 8801 SA / JE

8.8. Connection with Typical Microcontroller

Note

D1: Schottky Barrier

Diode

V DD

SCL

SDA

I

2

C-BUS

Master

V DD

SCL

RX-8801

SLAVE ADRS = 0110 010*

SDA

GND

Pull up Registor

R = t r

C

BUS

V DD

SCL SDA

( I 2 C Bus )

Note : It uses the secondary battery or a lithium battery. When using the seconding battery, the diode is not required.

When using the lithium battery, the diode is required.

For detailed value on the resistance, please consult a battery maker.

8.9. When used as a clock source (32 kHz-TCXO)

RX-8801

V

DD

V

DD

32.768kHz

O E

T1

SCL

SDA

V DD

TEST

T2

FOUT

/INT

FOE

GND

0.1 μF

Page - 27 ETM26E-03

RX − 8801 SA / JE

9. External Dimensions / Marking Layout

9.1. RX − 8801 SA ( SOP − 14pin )

9.1.1. External dimensions

RX − 8801 SA ( SOP − 14pin )

• External dimensions • Recommended soldering pattern

#14

10.1 ± 0.2

#8

0 ° - 10°

1.4

#1

0.35

5.0 7.4 ± 0.2

#7

0.05

Min. 3.2

± 0.1

1.27 1.2

0.15

0.6

5.4

1.4

1.27 0.7

1.27 × 6 = 7.62

Unit : mm

∗ The cylinder of the crystal oscillator can be seen in this area ( front ),

but it has no affect on the performance of the device.

9.1.2. Marking layout

RX − 8801 SA ( SOP − 14pin )

Type

R 8801

E A123B

Logo Production lot

∗ Contents displayed indicate the general markings and display, but are not the standards for the fonts, sizes and positioning.

Page - 28 ETM26E-03

RX − 8801 SA / JE

9.2. RX − 8801 JE ( VSOJ − 20pin )

9.2.1. External dimensions

RX − 8801 JE ( VSOJ − 20pin )

• External dimensions • Recommended soldering pattern

7.0 ± 0.3

#20 #11

(0.75)

1.5

#1 #10

5.4 6.0 ± 0.2

(0.75)

3.8

0.65

1.5

0.65 × 9 = 5.85

0.35

0.3

0.22 0.65

1.3 1.5 Max.

0 Min.

0.12 0.1 Unit : mm

∗ The cylinder of the liquid crystal oscillator can be seen in this area ( back and front ),

but it has no affect on the performance of the device.

9.2.2. Marking layout

RX − 8801 JE ( VSOJ − 20pin )

Type

R 8801

E A123B

Logo Production lot

∗ Contents displayed indicate the general markings and display, but are not the standards for the fonts, sizes and positioning.

Page - 29 ETM26E-03

RX − 8801 SA / JE

10. Application notes

1) Notes on handling

This module uses a C-MOS IC to realize low power consumption. Carefully note the following cautions when handling.

(1) Static electricity

While this module has built-in circuitry designed to protect it against electrostatic discharge, the chip could still be damaged by a large discharge of static electricity. Containers used for packing and transport should be constructed of conductive materials.

In addition, only soldering irons, measurement circuits, and other such devices which do not leak high voltage should be used with this module, which should also be grounded when such devices are being used.

(2) Noise

If a signal with excessive external noise is applied to the power supply or input pins, the device may malfunction or "latch up."

In order to ensure stable operation, connect a filter capacitor (preferably ceramic) of greater that 0.1

μF as close as possible to the power supply pins (between VDD and GNDs). Also, avoid placing any device that generates high level of electronic noise near this module.

* Do not connect signal lines to the shaded area in the figure shown in Fig. 1 and, if possible, embed this area in a GND land.

(3) Voltage levels of input pins

When the input pins are at the mid-level, this will cause increased current consumption and a reduced noise margin, and can impair the functioning of the device. Therefore, try as much as possible to apply the voltage level close to VDD or GND.

(4) Handling of unused pins

Since the input impedance of the input pins is extremely high, operating the device with these pins in the open circuit state can lead to unstable voltage level and malfunctions due to noise. Therefore, pull-up or pull-down resistors should be provided for all unused input pins.

2) Notes on packaging

(1) Soldering heat resistance.

If the temperature within the package exceeds +260 °C, the characteristics of the crystal oscillator will be degraded and it may be damaged. The reflow conditions within our reflow profile is recommended. Therefore, always check the mounting temperature and time before mounting this device. Also, check again if the mounting conditions are later changed.

* See Fig. 2 profile for our evaluation of Soldering heat resistance for reference.

(2) Mounting equipment

While this module can be used with general-purpose mounting equipment, the internal crystal oscillator may be damaged in some circumstances, depending on the equipment and conditions. Therefore, be sure to check this. In addition, if the mounting conditions are later changed, the same check should be performed again.

(3) Ultrasonic cleaning

Depending on the usage conditions, there is a possibility that the crystal oscillator will be damaged by resonance during ultrasonic cleaning. Since the conditions under which ultrasonic cleaning is carried out (the type of cleaner, power level, time, state of the inside of the cleaning vessel, etc.) vary widely, this device is not warranted against damage during ultrasonic cleaning.

(4) Mounting orientation

This device can be damaged if it is mounted in the wrong orientation. Always confirm the orientation of the device before mounting.

(5) Leakage between pins

Leakage between pins may occur if the power is turned on while the device has condensation or dirt on it. Make sure the device is dry and clean before supplying power to it.

Fig. 1 : Example GND Pattern

RX - 8801 SA

RX - 8801 JE

∗ The shaded part ( ) indicates where a GND pattern should be set without getting too close to a signal line

Fig. 2 : Reference profile for our evaluation of Soldering heat resistance.

Temperature [ °C ]

300

250

200

150

100

50

0

TP ; +260 °C OVER

+255 °C

TL ; +217 °C

Ts max ; +200 °C

Ts min ; +150 °C

60

Avg. Ramp-up

+3 °C / s Max. ts

60 s to 180 s

( +150 °C to +200 °C )

Time +25 °C to Peak tp ; 20 s to 40 s tL

60 s to 150 s

( +217 °C over )

−6 °C / s Max.

120 180 240 300 360 420 480 540 600 660 720 780

Time [ s ]

Page - 30 ETM26E-03

Application Manual

AMERICA

EPSON ELECTRONICS AM ERICA, INC.

HEADQUARTER 2580 Orchard Parkway, San Jose, CA 95131, U.S.A.

Phone: (1)800-228-3964 (Toll free) : (1)408-922-0200 (Main)

Fax: (1)408-922-0238 http://www.eea.epson.com

Atlanta Office One Crown Center 1895 Phoenix Blvd. Suite 348 Atlanta,GA 30349

Phone: (1)800-228-3964 (Toll free) : (1)770-907-7667 (Main)

Fax: (1)781-246-5443

Chicago Office 1827 Walden Office Square. Suite 450 Schaumburg, IL 60173

Phone: (1)847-925-8350

Fax: (1)847 925-8965

El Segundo Office 1960 E. Grand Ave., 2nd Floor, El Segundo, CA 90245, U.S.A.

Phone: (1)800-249-7730 (Toll free) : (1)310-955-5300 (Main)

Fax: (1)310-955-5400

EUROPE

EPSON EUROPE ELECTRONICS GmbH

HEADQUARTER Riesstrasse 15, 80992 Munich, Germany

Phone: (49)-(0)89-14005-0 Fax: (49)-(0)89-14005-110 http://www.epson-electronics.de

ASIA

EPSON (China) CO., LTD.

7F, Jinbao Building No.89 Jinbao Street Dongcheng District, Beijing, China, 100005

Phone: (86) 10-8522-1199 Fax: (86) 10-8522-1120 http://www.epson.com.cn

Shanghai Branch High-Tech Building,900 Yishan Road Shanghai 200233,China

Phone: (86) 21-5423-5577 Fax: (86) 21-5423-4677

Shenzhen Branch 12/F, Dawning Mansion,#12 Keji South Road, Hi-Tech Park,Shenzhen, China

Phone: (86) 755-26993828 Fax: (86) 755-26993838

EPSON HONG KONG LTD.

20/F., Harbour Centre, 25 Harbour Road, Wanchai,Hong kong

Phone: (852) 2585-4600 Fax: (852) 2827-2152 http://www.epson.com.hk

EPSON TAIWAN TECHNOLOGY & TRADING LTD.

14F, No.7, Song Ren Road, Taipei 110

Phone: (886) 2-8786-6688 Fax: (886)2-8786-6660 http://www.epson.com.tw

EPSON SINGAPORE PTE. LTD.

No 1 HarbourFront Place, #03-02 HarbourFront Tower One, Singapore 098633.

Phone: (65)- 6586-5500 Fax: (65) 6271-3182 http://www.epson.com.sg

SEIKO EPSON CORPORATION KOREA Office

50F, KLI 63 Building,60 Yoido-dong, Youngdeungpo-Ku, Seoul, 150-763, Korea

Phone: (82) 2-784-6027 Fax: (82) 2-767-3677 http://www.epson-device.co.kr

Gumi Branch Office 2F, Grand Bldg,457-4, Songjeong-dong Gumi-City,Gyongsangbuk-Do,

730-090, Korea

Phone: (82) 54-454-6027 Fax: (82) 54-454-6093

Distributor

Electronic devices information on WWW server http://www.epsontoyocom.co.jp

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