scp1000_product_family_specification_rev_0.08.pdf

scp1000_product_family_specification_rev_0.08.pdf
Doc.Nr. 8260800.08
Product Family Specification
SCP1000 Series
Absolute pressure sensor
SCP1000-D01
SCP1000-D11
SCP1000 Series
Note: Reader is advised to notice that this Product Family Specification applies to SCP1000 having updated
signal conditioning circuitry. This version can be recognized from the D01 or D11 marking on the top of the
component (see image). If you are using old SCP1000 version (marked using P01 or P03), please use Product
Family Specification rev. 0.06. Differences between the old and new SCP1000 version are described in Technical
Note 59 (SCP1000 ASIC Update).
Product marking
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Table of Contents
1 General Description ............................................................................................................5
1.1
Introduction ................................................................................................................................5
1.2 Functional Description ..............................................................................................................5
1.2.1 Sensing element....................................................................................................................5
1.2.2 Interface IC............................................................................................................................5
1.2.3 Factory calibration .................................................................................................................6
1.2.4 Supported features................................................................................................................6
1.2.5 Operation...............................................................................................................................6
1.2.5.1 High resolution measurement .........................................................................................6
1.2.5.2 High speed measurement...............................................................................................6
1.2.5.3 Ultra low power measurement ........................................................................................6
1.2.5.4 Low power measurement with external trigger ...............................................................6
1.2.5.5 Temperature output ........................................................................................................6
2 Start-up, Operation Modes, HW functions and Clock ......................................................7
2.1 Start-up .......................................................................................................................................7
2.1.1 Power down-pin (PD) during start-up (Phase 1) ...................................................................8
2.1.2 SCP1000 initialization during start-up (Phase 2)...................................................................8
2.1.2.1 SCP1000 initialization status check (optional) ................................................................8
2.1.2.2 SCP1000 checksum error check (optional) ....................................................................9
2.2 Measurement Modes .................................................................................................................9
2.2.1 Measurement modes timing and real time constraints..........................................................9
2.2.1.1 Continuous measurement modes ...................................................................................9
2.2.1.2 Triggered (low power) measurement mode ..................................................................10
2.2.2 Measurement mode selection .............................................................................................10
2.2.2.1 Switching between measurement modes .....................................................................11
2.2.3 Reading the pressure and temperature...............................................................................11
2.2.3.1 Examples of temperature conversion to [°C] ................................................................12
2.2.4 Measurement mode details .................................................................................................13
2.2.4.1 High resolution measurement mode .............................................................................13
2.2.4.2 High speed measurement mode...................................................................................14
2.2.4.3 Ultra low power measurement mode ............................................................................14
2.2.4.4 Low power measurement mode....................................................................................15
2.3
Over Pressure ..........................................................................................................................16
2.4
DRDY – data ready pin ............................................................................................................16
2.5
TRIG – trigger pin.....................................................................................................................16
2.6
Power Down Mode and PD Pin ...............................................................................................16
2.7
Standby Mode ..........................................................................................................................16
2.8
Reset .........................................................................................................................................16
2.9
Clock .........................................................................................................................................16
3 Addressing Space .............................................................................................................17
3.1
Register Description................................................................................................................17
3.2
Direct Access Registers..........................................................................................................17
3.3
Indirect Access Registers .......................................................................................................20
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3.3.1
Example of indirect access register write and read operations ...........................................21
3.4 EEPROM memory ....................................................................................................................21
3.4.1 EEPROM writing .................................................................................................................22
3.4.2 EEPROM reading................................................................................................................22
4 Serial Interfaces ................................................................................................................23
4.1 SPI Interface .............................................................................................................................23
4.1.1 SPI frame format .................................................................................................................23
4.1.2 Examples of SPI communication.........................................................................................24
4.2 TWI Interface ............................................................................................................................25
4.2.1 TWI frame format ................................................................................................................25
4.2.1.1 TWI write sequence ......................................................................................................26
4.2.1.2 8 bit TWI read sequence...............................................................................................27
4.2.1.3 16 bit TWI read sequence.............................................................................................27
5 Electrical Characteristics .................................................................................................29
5.1
Absolute Maximum Ratings....................................................................................................29
5.2
Power Supply ...........................................................................................................................29
5.3 Digital I/O Specification...........................................................................................................29
5.3.1 Digital I/O characteristics.....................................................................................................29
5.3.2 SPI AC characteristics.........................................................................................................30
5.3.3 TWI AC characteristics........................................................................................................31
6 Package Characteristics...................................................................................................32
6.1
Dimensions...............................................................................................................................32
7 Application Information ....................................................................................................33
7.1
Pin Description.........................................................................................................................33
7.2
Recommended Circuit Diagrams ...........................................................................................34
7.3
Recommended PWB Layout ...................................................................................................34
7.4
Assembly instructions ............................................................................................................36
7.5
Tape and reel specifications...................................................................................................36
7.6
Example flex print design .......................................................................................................36
8 Document Revision History .............................................................................................37
9 Contact Information ..........................................................................................................37
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1
General Description
1.1
Introduction
SCP1000 is pressure sensor that measures absolute pressure. The sensor consists of a silicon
bulk micro machined sensing element chip and a signal conditioning ASIC. The pressure sensor
element and the ASIC are mounted inside a plastic pre-moulded package and wire bonded to
appropriate contacts. The round shaped sensor component has 18 SMD solderable contacts.
SCP1000 block diagram is presented in Figure 1 below.
Sensing
element
Computation block
ADC
Temperature
measurement
Pressure calculation
and linearization
Clock
generator
Temperature
compensation
ASIC
control
block
EEPROM
Serial interface
SPI or TWI
To MCU
Figure 1. SCP1000 system level block diagram.
1.2
Functional Description
The SCP1000 performs almost complete data processing on-chip. The pressure and temperature
output data are calibrated and compensated internally. The only operations over the output data
required to obtain the pressure in [Pa] and the temperature in [°C] is single multiplication with
constants, see more details in section 2.2.3.
1.2.1
Sensing element
The sensing element is manufactured using the proprietary bulk 3D-MEMS process of VTI enabling
robust, stable, low noise and low power capacitive sensors.
Absolute pressure sensor element consists of a silicon wafer that is locally thinned to form a
pressure sensitive diaphragm. The diaphragm acts as a movable plate of the capacitive sensor.
The stationary plate is a thin film metal deposited on a second, glass coated silicon wafer. The
wafers are joined by anodic bonding so that a hermetically enclosed space is formed between
them. The diaphragm deflects due to the pressure difference between the exterior of the sensor
and the internal vacuum reference chamber.
1.2.2
Interface IC
The communication between the SCP1000 and its host micro-controller (µC) is based on a serial
interface, an interrupt line and specialized pins used to trigger special functions. The serial
interface allows registers' read and write operations and the interrupt line signals events, which
require host intervention. Two different serial interfaces are available: SPI and TWI (TWI is very
similar to I2C bus). The appropriate communication interface is pre-programmed in the factory. The
register access protocol is independent on the selected interface.
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1.2.3
Factory calibration
All sensors are factory calibrated. Some of the calibration parameters are: sensitivity to pressure,
offset, temperature sensitivity and temperature compensation. Calibration parameters will be read
automatically from the internal non-volatile during the start-up of the sensor.
1.2.4
Supported features
SCP1000 different versions and supported features are presented in Table 1 below.
Table 1. SCP1000 versions.
Features
SCP1000-D01
Supply voltage
Measuring range
Resolution
1
Interface
SCP1000-D11
2.4 V – 3.3 V
2.4 V – 3.3 V
30 kPa – 120kPa
30 kPa – 120kPa
1.5 Pa
1.5 Pa
SPI max 500 kHz
TWI max 400 kHz
Yes
Yes
Temperature output
Clock
Internal
Internal
Marking on top of
D01
D11
component
1
typical value in high resolution measurement mode
1.2.5
Operation
The SCP1000 pressure sensor has 4 measurement modes plus standby and power down mode. In
all measurement modes, the pressure output word-length is 19 bits and the temperature output
word-length is 14 bits.
1.2.5.1
High resolution measurement
In the high-resolution measurement mode the pressure is measured continuously with the highest
resolution and the output data refresh rate is typically 1.8 Hz.
1.2.5.2
High speed measurement
In the high speed measurement mode the measurements are performed continuously as well and
the conversion time is shortened at the cost of output resolution. This allows for an increase of the
output data refresh rate up approximately 9 Hz.
1.2.5.3
Ultra low power measurement
In the ultra low power measurement mode the device performs periodic measurements with the
lowest resolution (15 bits) and switches to standby mode between the measurements. In this mode
the updated pressure data is available approximately once per second.
1.2.5.4
Low power measurement with external trigger
In the low power measurement mode the device stays in standby mode and is ready to perform
single measurement using the selected resolution, 15 bits or 17 bits. After the measurement is
complete and the output data is refreshed, the sensor switches back to standby mode. Average
current consumption in low power mode depends on measurement resolution and trigger
frequency.
1.2.5.5
Temperature output
Temperature information is available in every measurement mode for each pressure measurement.
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2
2.1
Start-up, Operation Modes, HW functions and Clock
Start-up
The SCP1000 initialization sequence described in this section (and in Figure 2) is performed each
time the sensor is:
- powered up,
- waking up from power down mode
- waking up after reset.
During the start-up the power supplies must stabilize in to specified range before configuration and
calibration data can be loaded from the non-volatile memory to volatile registers. The start-up
sequence is divided into 3 phases described below in Figure 2.
POWER OFF STATE
AVDD = DVDD = 0 V
All I/Os = 0 V
CSB = 0 V S1)
YES
Power
management
available?
POWER ON
AVDD = DVDD
PD = DVDD
CSB = DVDDS1)
NO
POWER ON &
START-UP
AVDD = DVDD
PD = 0 V
CSB = DVDDS1)
Phase 1, PD pin during
start-up, see section 2.1.1
Delay 1 ms S2)
START-UP
PD = 0 V
S1)
CSB = DVDD
Delay
60 ms
YES
Check start-up
status? S3)
NO
Phase 2, SCP1000 initialization,
start-up status check is optional,
see section 2.1.2
Delay
90 ms
See routine for
start-up status
check in Figure 3
S1)
SCP1000 is in standby
mode waiting for
measurement
command
S2)
Figure 2. SCP1000 start-up sequence.
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with SCP1000-D11 (TWI-bus) products (refer to Table
19 in section 7.2).
The delay immediately after powering the system is
needed in order to let the power supply and the voltage
over the filter capacitors to stabilize. If it is needed this
delay time can be increased.
Status check is optional, see section 2.1.2.
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SCP1000 Series
2.1.1
Power down-pin (PD) during start-up (Phase 1)
SCP1000 has an external power down (PD) pin. In case the system has power management
capabilities, it is recommended that during power up the PD pin is tied to DVDD – this way the
sensor is forced to remain in power down mode during the stabilization of the power supplies. After
approximately 1ms (or longer depending on the power supply stabilization time) the PD pin can be
switched to DVSS allowing the sensor to start the power up and the initialization procedure to
begin.
In case the system does not have power management capability the PD pin can be tied to DVSS.
2.1.2
SCP1000 initialization during start-up (Phase 2)
A 60 ms delay after the start-up (Phase 1 in Figure 2) is recommended. After the delay initialization
will be finished and all configuration registers are loaded with their default values. During the 60 ms
start-up delay there should not be any interface activity attempts.
Start-up status check is optional and can be replaced with 90 ms delay, see Figure 2.
The start-up status check includes EEPROM checksum error result check. The routine is described
in Figure 3 and in sections 2.1.2.1 and 2.1.2.2 below.
READ
STATUS register
0x07 N1)
Increment
loop counter
Delay 10 ms N3)
NO
LSB = 0
YES
Loop count
≥ MAX N2)
NO
YES
N1)
ERROR EXIT
start-up fail
READ
DATARD8
register N4)
N2)
NO
N3)
LSB = 1
YES
SCP1000 is in
standby mode
waiting for
measurement
command
ERROR EXIT
EEPROM
checksum error
N4)
See the status register details in section 3.2. LSB = ‘0’
means that start-up procedure is finished.
The maximum number of retries (MAX loop count)
depends entirely on the system design. The
recommended value is 6.
The recommended loop delay time can be changed
depending on the system design. The recommended
default value is 10 ms.
DATARD8 register has address 0x1F when using SPI
interface (SCP1000-D01) and 0x7F when using TWI
interface (SCP1000-D11). If the content of DATARD8 is
0x01, the EEPROM checksum is correct.
Figure 3. Routine for start-up status check (optional).
2.1.2.1
SCP1000 initialization status check (optional)
The STATUS register 0x07 (see Figure 3) can be read to verify that start-up procedure is finished.
If the STARTUP bit (LSB) of the STATUS register (0X07) is ‘0’, the start-up procedure is finished
successfully. If the STARTUP bit of the STATUS register is ‘1’, the start-up procedure is still
running.
If the start-up procedure is still running, it is advised to re-check the STATUS register after a delay.
A recommend delay is 10ms. If the start-up procedure is not finished after the additional delay, the
re-check procedure can be started again (see Figure 3). In order to avoid infinite loop in case of
sensor malfunction it is advisable to limit the maximum number of cycles. Recommended value is 6
cycles when using 10 ms additional delay. If the start-up procedure is not finished successfully after
the maximum number of STATUS register re-check cycles has expired, the start-up procedure has
failed.
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2.1.2.2
SCP1000 checksum error check (optional)
The DATARD8 register (address 0x1F when using SPI interface or 0x7F when using TWI interface)
can be read in order to check the EEPROM checksum error (see Figure 3). If the content of
DATARD8 is 0x00, EEPROM checksum calculation indicated an error and the start-up procedure is
failed. Correct EEPROM checksum calculation result is indicated by content of 0x01 in DATARD8.
2.2
Measurement Modes
SCP1000 pressure sensor measurement modes are presented in Table 2 below. In three of the
measurement modes SCP1000 samples pressure and temperature continuously. In low power
mode SCP1000 measures pressure and temperature once after the measurement is triggered.
Table 2. SCP1000 measurement modes.
Measurement
mode
Activation code
0x0A
17 bits
Continuous
High speed
0x09
15 bits
Continuous
0x0B
15 bits
Continuous
0x0C or TRIG pin
17 bits or 15 bits
Triggered
Low power
2.2.1.1
Measurement
type
High resolution
Ultra low power
2.2.1
Resolution
Measurement modes timing and real time constraints
Continuous measurement modes
In continuous measurement mode the output data is refreshed after each measurement and the
availability of the updated pressure and temperature data is signaled through the assertion of the
DRDY pin and a DRDY bit is set to ‘1’ in the STATUS register.
In Figure 4 is presented the timing diagram in the continuous measurement modes.
TRIG pin
SCP1000
Status
Output
Update
DRDY pin
Measurement and computation
TEMP
UPDATE
(No. N+1)
TMEAS
Measurement and computation
PRESSURE
UPDATE
(No. N+1)
TEMP
UPDATE
(No. N+2)
PRESSURE
UPDATE
(No. N+2)
TCLR
Interface
Activity
Figure 4. Timing diagram in continuous measurement mode.
In order to clear the DRDY signal, the host processor has to read the pressure output data. The
temperature output data is updated before the pressure output data, thus the time to service the
DRDY (TCLR in Figure 4) is shorter than the measurement and computation time (TMEAS in Figure 4).
In the case that the temperature data is not needed, the time for servicing the DRDY interrupt can
be extended. In any case, the DRDY interrupt must be serviced (the pressure data reading has to
be completed) before the next pressure data update.
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If, for some reason, the real time requirement is not met, the output data will be overwritten and an
RTERR error bit is set to ‘1’ in the STATUS register. In order to clear the error status, the host
processor has to read the output pressure data (this data can be invalid). Once the error has been
cleared, normal operation can be continued.
2.2.1.2
Triggered (low power) measurement mode
In triggered measurement mode (low power) SCP1000 stays in standby mode until measurement
is externally triggered, see section for more 2.2.4.4 details. The availability of updated pressure and
temperature data is signaled as in continuous measurement modes (through the assertion of the
DRDY pin and a DRDY bit is set to ‘1’ in the STATUS register).
In Figure 5 is presented the timing diagram in the low power measurement mode (triggered).
TRIG pin
SCP1000
Status
Output
Update
Standby
Measurement and computation
TEMP
UPDATE
STANDBY
PRESSURE
UPDATE
DRDY pin
Interface
Activity
Figure 5. Timing diagram in triggered measurement mode.
See section 2.2.1.1 for details of clearing the DRDY signal and avoiding real time error.
The DRDY interrupt request has to be cleared before the next trigger signal is applied (rising edge
at TRIG pin Figure 5).
2.2.2
Measurement mode selection
The selection and activation of the measurement mode is done by writing the corresponding mode
activation code (see Table 2) in to OPERATION register, see section 3.2 for register details. The
measurement mode selection and activation is illustrated in Figure 6 below.
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M1)
For details for low power
mode resolution please
refer to section 2.2.1.2.
M2)
For details for DRDY
signal please see Figure
4, Figure 5 and section
2.3.
M3)
See section 2.2.3 for
more details of reading
the
pressure
and
temperature
Figure 6. SCP1000 measurement mode selection.
2.2.2.1
Switching between measurement modes
In order to switch between the measurement modes, it is necessary first to stop the active mode
before activating the new one by writing 0x00 in to OPERATION register. This will instruct
SCP1000 to cancel the current operation (SCP1000 enters in to standby mode). After writing 0x00
to OPERATION register and before new measurement mode is activated there should be a 50 ms
delay. Instead of the 50 ms delay, OPSTATUS register can be read. If OPSTATUS bit in
OPSTATUS register is ‘0’, new measurement mode can be activated as described in section 2.2.2
above (see Figure 6).
In order to avoid a real time error, it is strongly recommended to verify that the DRDY signal is low
(no new data) before activating new mode. If DRDY is high it is necessary to read the output data
before activating new measurement mode.
2.2.3
Reading the pressure and temperature
After the DRDY pin has signaled the availability of new measurement data, it is recommended that
the output data is read immediately in the following order:
o read the TEMPOUT register (temperature data in bits [13:0] – in case the temperature data
is not needed this step can be omitted).
o read the DATARD8 register (bits [2:0] contain the MSB of the pressure data)
o read the DATARD16 register (contains the 16 LSB of the pressure data)
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For more details of pressure data bit level description, see section 3.2 (Table 12). Pressure data is
presented in integer format. When operating within the nominal operation range (30…120 kPa) the
output of the SCP1000 changes between 120000 and 480000. The output is converted from
decimal format to [Pa] as follows:
Equation 1
Pres[ Pa] =
Pres[dec]
= 0.25 ⋅ Pres[dec] ,
4
where Pres[dec] is pressure read from SCP1000 in decimal format.
See section 3.1 (Table 13) for details more of temperature data bit level description. Temperature
data is presented in 2’s complement format and is converted from decimal format to [°C] as follows:
Equation 2
Temp[°C ] =
Temp[dec]
= 0.05 ⋅ Temp[dec]
20
where Temp[dec] is temperature read from SCP1000 in decimal format.
2.2.3.1
Examples of temperature conversion to [°C]
In case the sign bit is zero, '0' (see Table 3), the TEMPOUT binary value is converted to decimal
value and then to [°C] as follows:
Table 3. An example TEMPOUT bit pattern of a positive temperature data.
An example TEMPOUT bit pattern for positive temperature
Bit#
B15
B14
~[°C]
Data
x
bit #
TEMPOUT,
raw data
x
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
s
204.8
102.4
51.2
25.6
12.8
6.4
3.2
1.6
0.8
0.4
0.2
0.1
0.05
s
T12
T11
T10
T9
T8
T7
T6
T5
T4
T3
T2
T1
T0
0
0
0
0
1
0
0
0
1
0
1
1
1
0
s = sign bit
x = not used bit
The example binary value presented in Table 3 can be converted normally to decimal value
because the sign bit is zero:
bin '00 0010 0010 1110' → dec '558'
→ conversion to [°C]: 558/20 = 27,9 °C
In case the sign bit is one, '1' (see Table 4), the TEMPOUT binary value is converted to decimal
value and then to [°C] as follows (notice 2’s complement format):
Table 4. An example TEMPOUT bit pattern of a negative temperature data.
An example TEMPOUT bit pattern for negative temperature
Bit#
B15
B14
B13
~[°C]
s
Data
x
x
s
bit #
TEMPOUT,
1
raw data
TEMPOUT,
0
inverted data
Add '1' (one LSB) to inverted
TEMPOUT data
Absolute value for
0
TEMPOUT data
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
204.8
102.4
51.2
25.6
12.8
6.4
3.2
1.6
0.8
0.4
0.2
0.1
0.05
T12
T11
T10
T9
T8
T7
T6
T5
T4
T3
T2
T1
T0
1
1
1
1
1
1
0
0
1
0
1
0
0
0
0
0
0
0
0
1
1
0
1
0
1
1
+1
0
0
0
0
0
0
1
1
0
1
1
0
0
s = sign bit
x = not used bit
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The raw TEMPOUT data (bin '11 1111 1001 0100') is not converted to decimal value
because the sign bit is '1'. The bit pattern is first inverted (bin '00 0000 0110 1011') and
then 1 LSB is added to the inverted bit pattern. The resulting bit pattern is presented in the
last row of Table 4 (Absolute value for TEMPOUT data), which is converted normally to
decimal value:
bin '00 0000 0110 1100' → dec '108' → dec '-108' (because sign bit is '1')
→ conversion to [°C]: -108/20 = -5,4 °C
2.2.4
Measurement mode details
In this section all measurement modes are described in detail.
2.2.4.1
High resolution measurement mode
In high resolution measurement mode pressure and temperature are measured continuously with
the highest resolution. High resolution mode is activated by writing 0x0A in to OPERATION
register. Once the mode has been started the only interface activity required is periodic reading of
the output pressure and temperature registers (in applications where the temperature is not needed
the output temperature reading can be omitted), see section 2.2.1.1.
SCP1000 operation parameters in high resolution measurement mode are presented in Table 5
below.
Table 5. SCP1000 operation parameters in high resolution mode.
Symbol
Parameter
Vdd
Supply voltage (AVDD & DVDD)
Idd
Average supply current
25
µA
Pres
Pressure measurement resolution
17
bits
Tres
Temperature measurement
resolution
Pressure data output word-length
–
14
–
bits
–
19
–
bits
–
14
–
bits
Tmeas
Temperature data output wordlength
Measurement and computation time
Fmeas
Output data refresh rate
Tclr
Maximum time for servicing the
DRDY interrupt
PWL
TWL
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Max
Unit
2.4
2.7
3.3
V
500
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55
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2.0
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ms
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2.2.4.2
High speed measurement mode
In high speed measurement mode pressure and temperature are measured continuously the
conversion time is shortened at the cost of output resolution. This allows an increased output
refresh rate of approximately 9 Hz.
SCP1000 operation parameters in high speed measurement mode are presented in Table 6 below.
Table 6. SCP1000 operation parameters in high speed mode.
Symbol
Parameter
Vdd
Supply voltage (AVDD & DVDD)
Idd
Average supply current
Pres
Pressure measurement resolution
Tres
Temperature measurement
resolution
Pressure data output word-length
–
14
–
bits
–
19
–
bits
–
14
–
bits
Tmeas
Temperature data output wordlength
Measurement and computation time
Fmeas
Output data refresh rate
Tclr
Maximum time for servicing the
DRDY interrupt
PWL
TWL
2.2.4.3
Min
Typ
Max
2.4
2.7
3.3
25
bits
140
9
V
µA
15
7.9
Unit
ms
10.2
25
Hz
ms
Ultra low power measurement mode
In ultra low power measurement mode the device performs measurements continuously with the
lowest resolution (15 bits) and switches to standby mode between measurements. In this mode the
updated pressure data is available approximately once per second. The average current
consumption is in the range of 3.5 µA.
SCP1000 operation parameters in ultra low power measurement mode are presented in Table 7
below.
Table 7. SCP1000 operation parameters in ultra low power mode.
Symbol
Parameter
Vdd
Supply voltage (AVDD & DVDD)
Idd
Average supply current
3.5
µA
Pres
Pressure measurement resolution
15
bits
Tres
Temperature measurement
resolution
Pressure data output word-length
–
–
19
–
bits
Temperature data output wordlength
Output data refresh rate
–
14
–
bits
PWL
TWL
Fmeas
Tclr
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Typ
Max
Unit
2.4
2.7
3.3
V
Maximum time for servicing the
DRDY interrupt
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2.2.4.4
Low power measurement mode
In low power measurement mode SCP1000 stays in standby mode until measurement is externally
triggered. The measurement is triggered with rising edge of TRIG pin or by writing 0x0C to
OPERATION register. Low power measurement can be triggered after start-up and power down. If
some other measurement mode is activated, see section 2.2.2.1 for details of switching between
measurement modes.
The default measurement resolution for low power mode is 17 bits. Resolution can be configured to
15 bit or 17 bit mode through indirect CFG register (see section 3.3). The CFG register contents
are presented in Table 8 below.
Table 8. Recommended CFG register contents.
Resolution
CFG register content
17 bits (default)
0x05
15 bits
0x0D
SCP1000 operation parameters in low power measurement mode are presented in Table 9 below.
Table 9. SCP1000 operation parameters in low power mode.
Symbol
Parameter
Vdd
Supply voltage (AVDD & DVDD)
Idd
Average supply current
Pres
Pressure measurement resolution
Tres
Tmeas
Temperature measurement
resolution
Pressure data output word-length
Temperature data output wordlength
Measurement and computation time
Ftrig
Maximum trigger frequency
Tclr
Maximum time for servicing the
DRDY interrupt
PWL
TWL
Min
Typ
15 bits
17 bits
Max
Unit
2.4
2.7
3.3
V
1
Depends on
resolution and
trigger frequency
25
µA
15
17
bits
–
14
–
bits
–
–
19
14
–
–
bits
bits
140
500
ms
9
1.8
Hz
Before the next TRIG signal
-
Typical SCP1000 Current Consumption vs. Ext trigger frequency
in Low power mode
30
25
TYP. Idd [uA]
20
15
10
5
0
0
0.5
1
1.5
2
2.5
Trig Freq [Hz]
Figure 7. Typical current consumption in low power mode with 17 bit resolution.
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2.3
Over Pressure
When operating within the nominal operation range (30…120 kPa) the output of the SCP1000
changes between 120000 and 480000. In major over pressure situations (over 131 kPa), a sudden
drop of the output reading can be observed, since the SCP1000 pressure output is not limited.
2.4
DRDY – data ready pin
Availability of updated pressure and temperature data is signaled through the assertion of the
DRDY pin. DRDY is cleared after the DATARD16 register is read, see section 2.2.1 for more
detailed information.
2.5
TRIG – trigger pin
TRIG pin is used to trig the measurement in low power measurement mode (external trigger). The
µC has to actively drive the signal in high and low states. In applications where the TRIG signal is
not used it has be connected to DVSS. See section 2.2.4.4 for more detailed information.
2.6
Power Down Mode and PD Pin
In order to decrease further the current consumption in cases where there are long time intervals
between the measurements, SCP1000 has a built in power down mode, which can be activated
through the PD pin. SCP1000 will stay in power down mode as long as the PD signal is high. In
power down mode every digital output pin of SCP1000 tristates.
After PD signal changes back to low, SCP1000 powers up, performs initialization and is ready to
operate. Start-up sequence has to be executed always after power down mode, see section 2.1 for
more detailed information.
The advantage of using power down mode instead of switching off the supply is that during wakeup from power down there is no need to recharge the filter capacitors on AVDD and DVDD lines.
The µC has to actively drive the signal in high and low states. In applications where the PD signal
is not used it has to be connected to DVSS.
The current consumption of SCP1000 in power down mode is typically 0.2 µA.
2.7
Standby Mode
SCP1000 is in standby mode after start-up, when OPERATION register content is 0x00 and in ultra
low power measurement mode between the measurements. The average current consumption is in
the range of 1 µA.
2.8
Reset
SCP1000 ASIC software can be reseted by writing 0x01 in to RSTR register. After reset the RSTR
register content is set to 0x00 and the default values are loaded from EEPROM. The start-up
sequence should be followed from section 2.1.2 onwards after reset.
2.9
Clock
The SCP1000 pressure sensor is operated with internal clock, so external clock signal is not
needed.
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3
Addressing Space
SCP1000 register contents and bit definitions are described in more detail in next sections. All
registers are read and written through the serial host interface.
3.1
Register Description
SCP1000 register types:
- direct access registers,
- indirect access registers and
- EEPROM registers.
Table 10. List of SCP1000 direct and indirect access registers and EEPROM registers.
Address
SPI
TWI
Name
Description
0x00
REVID
ASIC revision number
0x01
DATAWR
0x02
R
Register
access
Direct
Indirect register access data
RW
Direct
8
8
ADDPTR
Indirect register access pointer
RW
Direct
8
0x03
OPERATION
Operation register
RW
Direct
8
0x04
OPSTATUS
Operation status
R
Direct
8
0x06
RSTR
ASIC software reset
W
Direct
8
0x07
STATUS
ASIC top-level status
R
8
R
Direct
Direct
R
Direct
16
0x1F
0x7F
DATARD8
0x20
0x80
DATARD16
0x81
0x21
Mode
TEMPOUT
Pressure output data (MSB) or
8 bit data read from EEPROM
Pressure output data (LSB) or
8-bit data read from indirect register
14-bit temperature output data
0x00
CFG
Configuration register
0x05
TWIADD
TWI address
0x29
USERDATA1
0x2A
USERDATA2
0x2B
USERDATA3
0x2C
USERDATA4
(R, W, RW)
Width[
bits]
8
R
Direct
16
RW
Indirect
W
Indirect
8
8
User data
RW
EEPROM
8
User data
RW
EEPROM
8
User data
RW
EEPROM
8
User data
RW
EEPROM
8
Register address in hex format.
RW – Read / Write register, R – Read only register.
3.2
Direct Access Registers
SCP1000 direct access register contents and bit definitions are described in this section. Direct
access registers can be accessed directly through the serial interface.
Address: 0x00
Register name: REVID, ASIC revision number
Initial
Bits
Mode
Name
Description
Value
7:0
R
03h
REVID
ASIC revision number
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Address: 0x01
Register name: DATAWR, indirect register data
Initial
Bits
Mode
Name
Description
Value
7:0
WR
00h
DATA
Indirect access data
Address: 0x02
Register name: ADDPTR, indirect register address (address pointer)
Initial
Bits
Mode
Name
Description
Value
7:0
WR
00h
ADDR
Indirect register address
Address: 0x03
Register name: OPERATION, operation register
Initial
Bits
Mode
Name
Description
Value
7:0
WR
00h
OPERATION See operation description in Table 11.
Table 11. Description for register contents in OPERATION register.
Operation
0x00
0x01
0x02
0x05
0x06
0x07
0x09
0x0A
0x0B
0x0C
0x0F
Others
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Description
No operation / cancel current operation (standby mode). Default value after
start-up, power down mode and reset.
Read indirect access register pointed by ADDPTR. Register contents is
available in DATARD16 in bits [7:0].
Write DATAWR contents in to the indirect access register pointed by
ADDPTR.
Read EEPROM register pointed by ADDPTR. Register contents is available
in DATARD8 in bits [7:0].
Write DATAWR contents in to the EEPROM register pointed by ADDPTR.
Perform INIT sequence: INIT values are downloaded from the EEPROM
to the processing unit. After the INIT sequence is over the INIT status is
present at DATARD8:
- DATARD8 = 0x01 → success
- DATARD8 = 0x00 → fail – checksum error
High speed acquisition mode start (continuous measurement).
Use operation 0x00 to stop the continuous acquisition
High resolution acquisition mode start (continuous measurement).
Use operation 0x00 to stop the continuous acquisition
Ultra low power acquisition mode start (continuous measurement).
Use operation 0x00 to stop the continuous acquisition
Low power acquisition start (perform single temperature and pressure
measurement, equivalent to external TRIG pin)
ASIC self test. After the self test is over the result is present at DATARD8:
- DATARD8 = 0x01 → self test successful
- DATARD8 = 0x00 → self test failed
Reserved
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Address: 0x04
Register name: OPSTATUS, operation status
Initial
Bits
Mode
Name
Description
Value
7:1
Reserved
0
R
0
OPSTATUS Operation status
0 – operation finished, results are available
1 – operation running
Address: 0x06
Register name: RSTR, ASIC software reset
Initial
Bits
Mode
Name
Value
7:0
W
0x00
RSTR
Description
ASIC software reset
0x00 – do not reset
0x01 – reset ASIC software (see section 2.8
for more details),
other combinations are reserved.
Address: 0x07
Register name: STATUS, ASIC top-level status
Initial
Bits
Mode
Name
Description
Value
7
Reserved
6
R
0
EXT
Status due external trigger
TRIGGED
0 – externally triggered acquisition is finished
1 – externally triggered acquisition is running
5
R
0
DRDY
Data ready (same behavior as DRDY-pin)
0 – no new results are available
1 – new results are available
4
R
0
RTERR
Real time error
0 – no real time error
1 – real time error (interrupt has not been
serviced in time, cleared by DATARD16
read operation)
3:1
Reserved
0
R
0
STARTUP
Start-up status
0 – start-up procedure is finished
1 – start-up procedure is running
SPI address: 0x1F
TWI address: 0x7F
Register name: DATARD8, pressure data MSB or 8 bit data read from EEPROM
Initial
Bits
Mode
Name
Description
Value
7:3
Reserved
2:0
R
000
PRES_MSB Pressure data MSB (3 bits)
7:0
R
00h
DATA
8 bit data from EEPROM register
If EEPROM register is read the content of the DATARD8 register is the EEPROM register content.
Otherwise pressure data MSB (bits [2:0]) can be read from DATARD8.
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SPI address: 0x20
TWI address: 0x80
Register name: DATARD16, pressure data LSB or 8 bit data read from indirect register
Initial
Bits
Mode
Name
Description
Value
15:0
R
0000h
PRES_LSB Pressure data LSB (16 bits)
15:8
Reserved
7:0
R
00h
DATA
8 bit data from indirect register
If indirect register is read the content of the DATARD16 register is the indirect register content (bits
[7:0]). Otherwise pressure data LSB (bits [15:0]) can be read from DATARD16.
Bit level description for pressure data from registers DATARD8 and DATARD16 is presented in
Table 12 below. Pressure information is presented in integer format. See section 2.2.3 (Equation 1)
for more detailed information of converting the pressure data in to Pascal, [Pa].
Table 12. Bit level description of pressure data.
DATARD8
Bit#
DATARD16
B2
B1
B0
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
~[Pa] 64K
Data
P18
bit #
32K
16K 8192 4096 2048 1024
B15
512
256
128
64
32
16
8
4
2
1
0.5
0.25
P17
P16
P11
P10
P9
P8
P7
P6
P5
P4
P3
P2
P1
P0
P15
B14
P14
B13
P13
P12
SPI address: 0x21
TWI address: 0x81
Register name: TEMPOUT, temperature in 2’s complement format
Initial
Bits
Mode
Name
Description
Value
15:14
Reserved
13:0
R
0000h
TEMP
Temperature output data
Bit level description for temperature data from register TEMPOUT is presented in Table 13 below.
See section 2.2.3 (Equation 2) for more detailed information of converting the temperature data in
to [°C].
Table 13. Bit level description of1 temperature data.
TEMPOUT
Bit#
~[°C]
Data
bit #
B15
B14
x
x
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
s
204.8
102.4
51.2
25.6
12.8
6.4
3.2
1.6
0.8
0.4
0.2
0.1
0.05
s
T12
T11
T10
T9
T8
T7
T6
T5
T4
T3
T2
T1
T0
s = sign bit
x = not used bit
3.3
Indirect Access Registers
SCP1000 indirect access register contents and bit definitions are described in this section. Indirect
access registers can be accessed through the serial interface using the OPERATION, DATAWR,
ADDPTR and DATARD16 registers (see section 3.3.1).
Address: 0x00
Register name: CFG, configuration register
Initial
Bits
Mode
Name
Value
7:0
RW
0x05
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Description, INDIRECT ACCESS
Low power mode resolution selection:
0x05 – high resolution selected (17 bits)
0x0D – low resolution selected (15 bits)
other combinations are reserved.
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Address: 0x05
Register name: TWIADD, TWI device address
Initial
Bits
Mode
Name
Description, INDIRECT ACCESS
Value
7:0
W
11h
TWIADD
TWI device address
3.3.1
Example of indirect access register write and read operations
Example of indirect access register WRITE operation (write 0x0D to indirect register CFG, 0x00):
o Write 0x00 in direct register ADDPTR (0x02)
o Write 0x0D in direct register DATAWR (0x01)
o Write 0x02 in direct register OPERATION (0x03)
o Wait 50 ms
Example of indirect access register READ operation (read indirect register CFG, 0x00):
o Write 0x00 in direct register ADDPTR (0x02)
o Write 0x01 in direct register OPERATION (0x03)
o Wait 5 ms
o Read direct register DATARD16 (0x20 for SPI, 0x80 for TWI), bits [15:8] should be treated
as zeros, the register content is in bits [7:0], see section 3.2 for further information.
3.4
EEPROM memory
SCP1000 has internal non-volatile memory for calibration and configuration data. Memory content
will be programmed during production. Initial configuration is loaded during sensor start-up.
EEPROM register contents and bit definitions are described in this section. User has access to 4
EEPROM registers. EEPROM registers can be accessed through the serial interface using the
OPERATION, DATAWR, ADDPTR and DATARD8 registers (see sections 3.4.1 and 3.4.2).
Address: 0x29
Register name: USERDATA1, user accessible EEPROM register
Initial
Bits
Mode
Name
Description
Value
7:0
RW
00h
USERDATA1 User accessible EEPROM register
Address: 0x2A
Register name: USERDATA2, user accessible EEPROM register
Initial
Bits
Mode
Name
Description
Value
7:0
RW
00h
USERDATA2 User accessible EEPROM register
Address: 0x2B
Register name: USERDATA3, user accessible EEPROM register
Initial
Bits
Mode
Name
Description
Value
7:0
RW
00h
USERDATA3 User accessible EEPROM register
Address: 0x2C
Register name: USERDATA4, user accessible EEPROM register
Initial
Bits
Mode
Name
Description
Value
7:0
RW
00h
USERDATA4 User accessible EEPROM register
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3.4.1
EEPROM writing
Please note that in order to guarantee reliable EEPROM writing operation it is very critical to follow
the requirements below. The minimum value for supply voltage at +25 °C temperature is 3.0 V
during EEPROM register write operation. The peak current consumption is also significantly higher
than in normal operation (~2 mA for 15 ms period per byte).
Example of WRITE operation to EEPROM register 0x29 (write 0xAA to EEPROM register 0x29):
o Write 0x29 in direct register ADDPTR (0x02)
o Write 0xAA in direct register DATAWR (0x01)
o Write 0x06 in direct register OPERATION (0x03)
o Wait 50 ms
3.4.2
EEPROM reading
The EEPROM can be read with nominal supply voltage, but the peak current consumption is
significantly higher than in normal operation (~1.5 mA for 20 µs period per byte).
Example of READ operation from EEPROM register 0x29 (read EEPROM register 0x29):
o Write 0x29 in direct register ADDPTR (0x02)
o Write 0x05 in direct register OPERATION (0x03)
o Wait 15 ms (minimum wait value)
o Read direct register DATARD8 (0x1F for SPI, 0x7F for TWI), the register content is in bits
[7:0], see section 3.2 for further information.
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4
Serial Interfaces
Communication between SCP1000 sensor and master controller is based on serial data transfer
and dedicated interrupt line (DRDY-pin). Depending on operation mode an external trigger pin
(TRIG) can also be used in serial interfacing. Two different serial interfaces are available for
SCP1000 sensor: SPI and TWI (very similar to I2C). However, only one interface per product is
enabled by pre-programming in the factory. SCP1000 acts as a slave on both SPI and TWI bus.
4.1
SPI Interface
The SPI interface is a full duplex 4 wire serial interface. The connection between the µC and
SCP1000 is done using MOSI, MISO, SCK and CSB. CSB selects the chip on multi-chip SPI bus,
SCK is the serial data clock, MOSI is the data line from master to slave (Master Out Slave In) and
MISO is data line from slave to master (Master In Slave Out). SCP1000 is configured to SPI slave
mode (see Figure 8).
Master µC
SCP1000
Figure 8. SPI master slave configuration.
4.1.1
SPI frame format
The SCP1000 SPI frame format is presented in Figure 9 below.
Figure 9. SPI frame format for two 8 bit words.
Each SPI communication frame contains two or three 8 bit words: the first word defines the register
address (6 bits wide, bits [A5:A0] in Figure 9) followed by the type of access (‘0’ = Read or
‘1’ = Write) and one zero bit (bit 0, LSB). The following word(s) contain the data being read or
written. The MSB of the words are sent first. Bits from MOSI line are sampled in on the rising edge
of SCK and bits to MISO line are latched out on falling edge of SCK.
The CSB line must stay low during the entire frame accesses, i.e. between the bytes. If the CSB
line state changes to high, the access is terminated. The CSB has to be pulled up after each
communication frame.
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4.1.2
Examples of SPI communication
Examples SPI communication (8 and 16 bit read / write operations) are presented in Figure 10
below.
Figure 10. SPI communication examples.
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4.2
TWI Interface
TWI is a 2-wire half-duplex serial interface. It consists of one master device and one or more slave
devices. The master is defined as a micro controller providing the serial clock (SCL), and the slave
as any integrated circuit receiving the SCL clock from the master. The SCP1000 sensor always
operates as a slave device in master-slave operation mode. When in SPI interface a hardware
addressing is used (slaves have dedicated CSB signals), the TWI interface uses a software based
addressing (slave devices have dedicated bit patterns as addresses). Seven bit device addressing
is used with SCP1000. The default TWI device address for SCP1000 is 0x11, b’001 0001’ (preprogrammed during SCP1000 production).
The two wires in TWI bus are:
o SCL, serial clock and
o SDA, bi-directional data line.
The SCL pin of SCP1000 is an input pin (SCP1000 never controls the SCL line). Data is
transferred in and out of the sensor through the bi-directional SDA pin. SDA has an open-drain
output, so an external pull-up resistor to DVDD is required (see Figure 11). The minimum value for
SDA pull-up resistor is 2 kΩ.
External pull-up resistor to DVDD
SCP1000 (Slave)
µC (Master)
SDA
TWI
SCL
Figure 11. TWI master slave configuration.
External pull-up resistor from SCL to DVDD is not needed if master drives SCL actively to high and
low states. There is no de-bouncing is implemented in the SCP1000 digital I/O pads, so the signals
on SDA and SCL must be clean.
4.2.1
TWI frame format
TWI transactions are based on a byte-long transfers separated by acknowledgements. Bits from
SDA line are sampled in on the rising edge of SCL and bits to SDA line are latched out on falling
edge of SCL. Master starts and stops the communication by sending start and stop bits. After start
bit master sends device TWI device address. The communication continues with predefined frame
format. General patterns of TWI frame format are described below.
START BIT (µC → SCP1000)
The start bit is a high to low transition on SDA, while SCL is high. When the master
issues a start bit, it takes the control of the bus.
SLAVE DEVICE ADDRESS (µC → SCP1000)
Master sends a 7 bit slave device address, bits [7:1], MSB first. SCP1000 device
address is 0x11, b’001 0001’ by default. The LSB (bit 0) indicates the type of access
(‘1’ = Read or ‘0’ = Write).
ACKNOWLEDGE BIT
The transmitter of the acknowledge bit must tie the SDA line to low to perform an
acknowledgement. The receiver of the acknowledge bit must release the SDA line
because at this time, it is not the master of the TWI bus. The receiver then checks
the acknowledge bit by reading a ‘0’ on SDA.
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REGISTER ADDRESS (µC → SCP1000)
Master sends register address to SCP1000 MSB first.
REGISTER DATA (SCP1000 → µC)
The SCP1000 registers can be 8 or 16 bits wide. An 8 bit write is performed by
sending MSB first. A 16 bits write is performed by sending two bytes (MSB first).
After each byte, the slave sends an acknowledgement bit.
STOP BIT (µC → SCP1000)
The stop bit is a low to high transition on SDA, while SCL is high. The master, who
has generated the stop bit, sets the bus free.
REPEATED START (µC → SCP1000)
A repeated start is a start signal generated by a master, which has already taken the
control of the TWI bus. It is used by the master to initiate a transfer with a new slave,
or with the same slave, in the other communication mode (transmit or receive mode),
without releasing the bus.
NOT ACKNOWLEGDE BIT:
If the receiver of the acknowledge bit reads a ‘1’ on SDA line during an acknowledge
clock pulse, that means transmitter did not acknowledge. The master uses the not
acknowledge bit to terminate a read action.
4.2.1.1
TWI write sequence
8 bit TWI write sequence is presented in Figure 13 and described below:
1. START BIT (to initiate a transmission, the master sends a start bit)
2. SLAVE DEVICE ADDRESS (slave device address with WRITE access → LSB = ‘0’)
3. SLAVE ACKNOWLEDGEMENT (having identified device address as its own, slave
acknowledges by sending an acknowledge bit)
4. REGISTER ADDRESS (the 8 bit address of the register to be written, MSB first)
5. SLAVE ACKNOWLEDGEMENT (the slave sends an acknowledgement bit)
6. REGISTER DATA (master sends the data to be written to the addressed register)
7. SLAVE ACKNOWLEDGEMENT (after receiving the byte, the slave sends an
acknowledgement bit)
8. STOP BIT (master sets the bus free)
1.
5.
3.
2.
4.
7.
8.
6.
Figure 13. TWI frame format for 8 bit write operation (numbers from 1 to 8 refer to list above).
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4.2.1.2
8 bit TWI read sequence
8 bit TWI read sequence is presented in Figure 14 and described below:
9. START BIT (to initiate a transmission, the master sends a start bit)
10. SLAVE DEVICE ADDRESS (slave device address with WRITE access → LSB = ‘0’)
11. SLAVE ACKNOWLEDGEMENT (having identified device address as its own, slave
acknowledges by sending an acknowledge bit)
12. REGISTER ADDRESS (the 8 bit address of the register to be read, MSB first)
13. SLAVE ACKNOWLEDGEMENT (the slave sends an acknowledgement bit)
14. REPEATED START (from master)
15. SLAVE DEVICE ADDRESS (slave device address with READ access → LSB = ‘1’)
16. SLAVE ACKNOWLEDGEMENT (the slave acknowledges)
17. REGISTER DATA (the master continues sending the SCK pulses as slave sends the
defined register content to SDA line)
18. MASTER NOT ACKNOWLEDGE (master terminates the data transfer by sending not
acknowledge bit)
19. STOP BIT (master sets the bus free)
9.
13. 14.
11.
10.
15.
12.
18. 19.
16.
17.
Figure 14. TWI frame format for 8 bit read operation (numbers from 9 to 19 refer to list
4.2.1.3
16 bit TWI read sequence
16 bit TWI read sequence is presented in Figure 15 and described below:
20. START BIT (to initiate a transmission, the master sends a start bit)
21. SLAVE DEVICE ADDRESS (slave device address with WRITE access → LSB = ‘0’)
22. SLAVE ACKNOWLEDGEMENT (having identified device address as its own, slave
acknowledges by sending an acknowledge bit)
23. REGISTER ADDRESS (the 8 bit address of the register to be read, MSB first)
24. SLAVE ACKNOWLEDGEMENT (the slave sends an acknowledgement bit)
25. REPEATED START (from master)
26. SLAVE DEVICE ADDRESS (slave device address with READ access → LSB = ‘1’)
27. SLAVE ACKNOWLEDGEMENT (the slave acknowledges)
28. MSB BYTE OF REGISTER DATA (the master continues sending the SCK pulses as slave
sends the defined register MSB content to SDA line)
29. MASTER ACKNOWLEDGEMENT (the master acknowledges after it has received the first
8 bit byte of register content)
30. LSB BYTE OF REGISTER DATA (the master continues sending the SCK pulses as slave
sends the defined register LSB content to SDA line)
31. MASTER NOT ACKNOWLEDGE (master terminates the data transfer by sending not
acknowledge bit)
32. STOP BIT (master sets the bus free)
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SCP1000 Series
20.
24. 25.
22.
21.
23.
27.
26.
31. 32.
29.
28.
30.
Figure 15. TWI frame format for 16 bit read operation (numbers from 20 to 32 refer to list above).
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SCP1000 Series
5
Electrical Characteristics
5.1
Absolute Maximum Ratings
The absolute maximum ratings of SCP1000 are presented in Table 14 below.
Table 14. Absolute maximum ratings of SCP1000.
Parameter
Supply voltage (Vdd)
Voltage at input / output pins1
ESD (Human body model)
Storage temperature
Proof pressure
Ultrasonic cleaning
Value
-0.3 to +3.6
-0.3 to (Vdd + 0.3)
±2.0
-30 … +85
2.0
Not allowed
Unit
V
V
kV
°C
MPa
1
Referred to DVDD
5.2
Power Supply
The analog and digital supply voltage levels (AVDD and DVDD) should always be equal.
5.3
5.3.1
Digital I/O Specification
Digital I/O characteristics
SCP1000 has no pull-up/down resistors in any pins.
Table 15. Characteristics of digital I/O pins.
Parameter
Conditions
Input: CSB, MOSI, SCK/SCL, TRIG, PD
Input high voltage
1
Input low voltage
2
Hysteresis
3
Absolute maximum value
4
of input peak current
Input capacitance
5
TRIG pulse width
Figure 16
6
Symbol
Min
VIH
VIL
VHYST
|Iin|
0.7*DVDD
VOH
VOL
|Iout|
Max
0.3*DVDD
0.1*DVDD
1
Cin
Twtrig
Output terminal: MISO/SDA, DRDY
Output high voltage
|Iout| = 1 mA
7
Output low voltage
|Iout| = 1 mA
8
Absolute value of output
9
current
10 Load capacitance
Typ
1.6
Cout
V
V
V
µA
pF
ns
200
0.8*DVDD
0
Unit
DVDD
0.2*DVDD
1
V
V
mA
50
pF
Twtrig
TRIG
Figure 16. TRIG pulse timing.
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SCP1000 Series
5.3.2
SPI AC characteristics
The AC characteristics of the SPI interface are defined below in Figure 17 and Table 16. All the
timing parameters are relative to 10% (falling edge) and 90% (rising edge) of signal maximum
level.
TLS1
TCH
TCL
TLS2
TLH
CSB
SCK
THOL
MOSI
TSET
MSB in
TVAL1
MISO
LSB in
DATA in
TVAL2
MSB out
TLZ
DATA out
LSB out
Figure 17. Timing diagram for SPI communication.
Table 16. AC characteristics of SPI communication.
Parameter
Conditions
Symbol
Min
Typ
Max
Unit
1 Time from CSB to SCK
2 Time from SCK to CSB
Terminal SCK
TLS1
TLS2
100
100
ns
ns
3 SCK low time
4 SCK high time
5 SCK Frequency
Terminal MOSI, SCK
TCL
TCH
Fsck
100
100
ns
ns
MHz
TSET
20
ns
THOL
20
ns
Terminal CSB, SCK
6
Time from MOSI to SCK. Data setup
time
7 Time from SCK to MOSI. Data hold
time
Terminal MISO, CSB
8
Time from CSB to stable MISO
9
Time from CSB to high impedance
state of
MISO
Terminal MISO, SCK
10
Time from SCK to stable MISO
1
Load
capacitance at
MISO < 20 pF
Load
capacitance at
MISO < 20 pF
TVAL1
100
ns
TLZ
100
ns
Load
capacitance at
MISO < 20 pF
TVAL2
50
ns
Terminal MOSI, CSB
11
Time between SPI cycles, CSB at
high level
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SCP1000 Series
5.3.3
TWI AC characteristics
The AC characteristics of the TWI interface are defined below in and. All the timing parameters are
relative to 10% (falling edge) and 90% (rising edge) of signal maximum level.
thigh
tlow
Start
Stop
tbuf
SCL
SDA
thdsta
tsudat
thddat
tsusta
tsusto
Figure 18. Timing diagram for TWI communication.
Table 17 AC characteristics of TWI communication.
1
2
3
4
5
6
7
8
9
Parameter
Hold time start condition
SCL frequency
SCL high
SCL low
Setup time for repeated start
Time from SCL to SDA: data hold
time
Time from SDA to SCL: data setup
Time from SCL to SDA: data hold
Bus free time between a START and
a STOP
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Symbol
Thdsta
Fscl
Thigh
Tlow
Tsusta
Thddat
Min
600
Typ
Max
1300
600
600
300
Unit
ns
kHz
ns
ns
ns
ns
Tsudat
Tsusto
Tbuf
100
600
1300
ns
ns
ns
400
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SCP1000 Series
6
6.1
Package Characteristics
Dimensions
SCP1000 package dimensions are presented in Figure 19 below (dimensions in [mm]).
Figure 19. SCP1000 package dimensions.
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SCP1000 Series
7
7.1
Application Information
Pin Description
SCP1000 pin numbers are presented in Figure 20 below and pin descriptions in Table 18. Dummy
pads in Figure 20 must be soldered also.
Pressure element location
Figure 20. SCP1000 pin numbers.
Table 18. SCP1000 pin description.
Pin #
1
2
Name
ATST
TRIG
3
4
5
6
7
8
DRDY
CLK
DVDD
DVSS
DVDDS
PD
9
10
11
12
13
14
15
16
SCK/SCL
MOSI/SDA
MISO
CSB
AVDD
AVSS
AVSS
ATST
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Connect to analog ground
Trigger input, connect to GND if
not used
Interrupt signal (data ready)
Connect to digital ground
Digital supply voltage
Digital ground
Digital supply voltage filter
Power down, connect to GND if
not used
SPI clock input, SCK
SPI data input, MOSI
SPI data output
SPI chip select
Analog supply voltage
Analog ground
Analog ground
Connect to analog ground
Subject to changes
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SCP1000-D11 (TWI)
Connect to analog ground
Trigger input, connect to GND if
not used
Interrupt signal (data ready)
Connect to digital ground
Digital supply voltage
Digital ground
Digital supply voltage filter
Power down, connect to GND if
not used
TWI serial clock input, SCL
TWI data input/output, SDA
Not connected
Connect to analog supply voltage
Analog supply voltage
Analog ground
Analog ground
Connect to analog ground
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SCP1000 Series
7.2
Recommended Circuit Diagrams
In order to achieve high performance and low noise level it is recommended both AVDD and DVDD
have their own supply voltage regulators and analog ground plane is separated from digital ground
plane near SCP1000. If high performance is not needed, DVDD and AVDD can be supplied from
one regulator. Recommended circuit diagrams for SCP1000 are presented in Table 19 below.
Table 19. SCP1000 recommended circuit diagrams.
TWI interface
Simplified (single supply)
High performance
SPI interface
In case PD or TRIG pins are not used, in order to decrease the number of connections, they can be
connected to GND, this way the minimum number of connections can be as low as 5 (VDD, GND,
SDA, SCL, DRDY).
Table 20. Recommended capacitor values for SCP1000 circuit diagrams presented in Table 19.
7.3
Capacitor
High performance
circuit diagrams
C1
C2
C3
470 nF
470 nF
100 nF
Minimum
requirements for
simplified circuit
diagrams
Minimum 200 nF
100 nF
10 nF
Recommended PWB Layout
General PWB layout recommendations for SCP1000 products (refer to Table 21):
1. Locate the ceramic SMD filtering capacitors right next to SCP1000 package.
2. Use plane for GND connection.
3. Connect the plane under SCP1000 to AGND.
4. Minimize the power supply/ground loops.
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Recommended PWB pad layout for SCP1000 is presented in Figure 21 below (dimensions in [mm],
tolerances ±0.05 mm).
Figure 21. Recommended PWB pad layout for SCP1000.
Recommended PWB layout for SCP1000 with SPI and TWI interfaces is presented in Table 21
below (circuit diagram presented in Table 19 above).
Table 21. SCP1000 recommended PWB layouts (not in real size, for reference only).
TWI interface
Simplified (single supply)
High performance
SPI interface
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SCP1000 Series
7.4
Assembly instructions
The Moisture Sensitivity Level (MSL) of the SCP1000 component is 3 according to the IPC/JEDEC
J-STD-020C. Please refer to the document "TN51 SCP1000 Assembly Instructions" for more
detailed information of SCP1000 assembly.
7.5
Tape and reel specifications
Please refer to the document "TN51 SCP1000 Assembly Instructions" for tape and reel
specifications.
7.6
Example flex print design
The electric connections between the SCP1000 sensor and electronics of an application can be
carried out by using a flex print. An example flex print design for SCP1000 is presented in Figure
22 and Figure 23 below. These flex print designs are designed by following the recommended
circuit diagrams and PWB layouts presented in sections 7.2 and 7.3).
VDD
DRDY
TRIG
GND
CSB
PD
MISO
MOSI
SCK
Figure 22. An example flex print design for SCP1000 with SPI connection (with and without
leads).
VDD
DRDY
GND
PD
SDA
SCL
Figure 23. An example flex print design for SCP1000 with TWI connection (with and without
leads).
Note the location of the filtering capacitors C1, C2 and C3. The used capacitor values are
presented in Table 20 (the high performance circuit values). The circuit diagrams for these flex print
designs are the presented in Table 19 (the single supply circuits). The example flex print is
designed with the min. 6 mils clearance and trace width. Vias are 0,3 mm and via pads are
0,55mm. The figures of both designs are from top view, the SCP1000 sensor is assembled in top
side of the flex print (top layer red, bottom layer blue). GND is connected as a plane throughout the
whole flex print from connector to SCP1000 sensor.
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SCP1000 Series
8
9
Document Revision History
Version
Date
Change Description
0.01
10.03.2006
0.02
27.04.2006
This document replaces the following SCP1000 documents:
- “SCP1000_operation_instructions”,
- “TN34_SCP1000_SPI_and_I2C_Interfaces”,
- “TN35_SCP1000-D01,D02 MISO Configurations” and
- “TN45_SCP1000_start_up_sequence”
Package characteristics / dimensions update
Recommended PWB layout update
0.03
22.05.2006
0.04
04.07.2006
0.05
30.08.2006
0.06
0.07
14.11.2006
14.11.2006
0.08
30.10.2007
Figure17 SCP1000 package dimensions picture update
Solder Instructions text update
Figure 19 Recommended PWB pad layout picture update
Changing the name of the document
Updated:
- Section "3.4.1 EEPROM writing "
- Section "5 Electrical characteristics"
- Section "6.2 Solder instructions" renamed to "7.4 Assembly instructions",
- Section "7.5 Tape and reel specifications" added
- Minor language corrections
Contact information
Minor updates in SCP1000 operation parameters, examples for temperature conversion to [°C]
added (section 2.2.3.1).
Minor updates in SCP1000 data refresh rates.
Updated for C-version asic:
- Section "2.1 Start-up"
- Section "2.3 Over Pressure Detection" (removed)
- Section "2.6 Power down mode"
- Section "3.1 Register description"
- Section "4.1 SPI Interface"
- Section "7.6 Example flex print design" added
Gel pockets added to SCP1000 package
Contact Information
Finland
(head office)
VTI Technologies Oy
P.O. Box 27
Myllynkivenkuja 6
FI-01621 Vantaa
Finland
Tel. +358 9 879 181
Fax +358 9 8791 8791
E-mail: [email protected]
Germany
VTI Technologies Oy
Branch Office Frankfurt
Rennbahnstrasse 72-74
D-60528 Frankfurt am Main,
Germany
Tel. +49 69 6786 880
Fax +49 69 6786 8829
E-mail: [email protected]
Japan
VTI Technologies Oy
Tokyo Office
Tokyo-to, Minato-ku 2-7-16
Bureau Toranomon 401
105-0001
Japan
Tel. +81 3 6277 6618
Fax +81 3 6277 6619
E-mail: [email protected]
China
VTI Technologies Shanghai Office
6th floor, Room 618
780 Cailun Lu
Pudong New Area
201203 Shanghai
P.R. China
Tel. +86 21 5132 0417
Fax +86 21 513 20 416
E-mail: [email protected]
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USA
VTI Technologies, Inc.
One Park Lane Blvd.
Suite 804 - East Tower
Dearborn, MI 48126
USA
Tel. +1 313 425 0850
Fax +1 313 425 0860
E-mail: [email protected]
To find out your local sales
representative visit www.vti.fi
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