MAX8882, MAX8883
19-1818; Rev 1; 10/01
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
Features
♦
♦
♦
♦
♦
♦
♦
Two LDOs in Tiny SOT23
Up to 160mA Output Current (each LDO)
40µVRMS Output Noise (MAX8882)
72mV Dropout at 80mA Load
Low 165µA Operating Supply Current
62dB PSRR (greater than 56dB to 100kHz)
Independent Low-Power Shutdown Controls
(MAX8883)
♦ Thermal-Overload and Short-Circuit Protection
♦ Output Current Limit
Selector Guide
VOUTA
VOUTB
MAX8882EUTJJ
2.85
2.85
AANR
MAX8882EUTAQ
3.3
2.5
AAPW
µP/DSP Core/IO Power
MAX8882EUTA5
3.3
1.8
AARY
Cellular and PCS Telephones
MAX8882EUTQ5
2.5
1.8
AAPX
PDAs and Palmtop Computers
MAX8882EUTGG
3.0
3.0
AAZT
Notebook Computers
MAX8883EUTJJ
2.85
2.85
AANS
Digital Cameras
MAX8883EUTAQ
3.3
2.5
AAPY
MAX8883EUTA5
3.3
1.8
AARZ
MAX8883EUTQ5
2.5
1.8
AAPZ
MAX8883EUTGG
3.0
3.0
AAZU
________________________Applications
Hand-Held Instruments
Pin Configurations
PART
TOP MARK
***Other combinations between 1.8V and 3.3V are available in
100mV increments. Contact factory for other versions.
Minimum order quantity is 50,000 units.
Ordering Information
TOP VIEW
OUTB 1
GND 2
6
MAX8882
5
PART
SHUTDOWN
TEMP
RANGE
PINPACKAGE
MAX8882EUT_ _*
Single
-40°C to +85°C
6 SOT23-6
MAX8883EUT_ _*
Dual
-40°C to +85°C
6 SOT23-6
OUTA
IN
*See Selector Guide
BP 3
4
Typical Operating Circuit
SHDN
SOT23-6
OUTA
VIN
2.5V to 6.5V
Pin Configurations continued at end of data sheet.
2.2µF
VOUTA
FIXED
(1.8V to 3.3V)
2.2µF
VOUTB
FIXED
(1.8V to 3.3V)
MAX8882
MAX8883
OUTB
SHDN_
IN
2.2µF
GND
(BP)
0.01µF
( ) ARE FOR MAX8882 ONLY.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX8882/MAX8883
General Description
The MAX8882/MAX8883 dual, low-noise, low-dropout
linear regulators operate from a +2.5V to +6.5V input
and deliver up to 160mA each of continuous current.
Both versions offer low output noise and low dropout of
only 72mV at 80mA. Designed with an internal Pchannel MOSFET pass transistor, the MAX8882/
MAX8883 maintain a low 165µA supply current (both
LDOs on), independent of the load current and dropout
voltage. Other features include short-circuit protection
and thermal-shutdown protection. The MAX8882 has a
single shutdown input and provides an external reference bypass pin to improve noise performance. The
MAX8883 includes two independent logic-controlled
shutdown inputs. The MAX8882/MAX8883 are both
available in a miniature 6-pin SOT23 package.
MAX8882/MAX8883
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
ABSOLUTE MAXIMUM RATINGS
IN, SHDN, SHDNA, SHDNB, BP to GND...............-0.3V to +7.0V
OUTA, OUTB to GND ..................................-0.3V to (VIN + 0.3V)
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (TA = +70°C)
6-Pin SOT23 (derate 8.7mW/°C above +70°C)............695mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VIN = +3.6V, SHDN = SHDNA = SHDNB = IN, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
CONDITIONS
MIN
Input Voltage
Undervoltage Lockout
Threshold
TYP
2.5
VIN_ rising, hysteresis 40mV typical
2.15
2.25
MAX
UNITS
6.5
V
2.40
V
TA = +25°C, IOUT_ = 1mA
-1
1
Output Voltage Accuracy
IOUT_ = 1mA
-2
2
-3
2
Maximum Output Current
Continuous
IOUT_ = 100µA to 160mA
160
Current Limit
Ground Current
Shutdown Supply Current
SHDN_ Input Threshold
SHDN_ Input Bias Current
Dropout Voltage
(Notes 2, 3)
Line Regulation
Output Voltage Noise
2
mA
160
550
No Load, VIN = 6.5V
165
IOUT_ = 80mA, both LDOs
170
SHDN_ = GND, TA = +25°C
0.01
SHDN_ = GND
0.1
VIH
265
1
1.6
VIL
0.4
SHDN_ = GND or IN, TA = +25°C
0
SHDN_ = GND or IN
100
0.05
IOUT_ = 1mA
1
IOUT_ = 40mA
36
IOUT_ = 80mA
72
144
0
0.2
VIN = (VOUT_ + 0.4V or 2.5V) to + 6.5V,
IOUT_ = 1mA
-0.2
%
10Hz to 100kHz, CBP = 0.01µF, COUT_ = 4.7µF,
IOUT_ = 1mA
MAX8882
40
10Hz to 100kHz, COUT_ = 4.7µF, IOUT_ = 10mA
MAX8883
320
_______________________________________________________________________________________
mA
µA
µA
V
nA
mV
%/V
µVRMS
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
(VIN = +3.6V, SHDN = SHDNA = SHDNB = IN, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
CONDITIONS
MIN
TYP
100Hz, CBP = 0.01µF, COUT_ = 4.7µF
MAX8882
62
100Hz, COUT_ = 4.7µF
MAX8883
60
MAX
UNITS
Output Voltage AC PSRR
dB
Thermal Shutdown
Temperature
160
°C
Thermal Shutdown
Hysteresis
10
°C
Note 1: All units are 100% production tested at TA = +25°C. Limits over the operating temperature range are
guaranteed by design.
Note 2: The dropout voltage is defined as VIN - VOUT when VIN = VOUT (NOM). Specification only applies when VOUT ≥ 2.5V.
Note 3: See the Typical Operating Characteristics for guaranteed specifications at voltages other than 3.3V.
Typical Operating Characteristics
(VOUT_ = 2.85V, IOUT_ = 80mA, VIN = +3.6V, COUT_ = 2.2µF, CBP = 0.01µF, and CIN = 2.2µF, unless otherwise noted.)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
SUPPLY CURRENT
vs. LOAD CURRENT
NO LOAD
100
50
0
140
120
100
80
60
1
2
3
4
5
100
80
60
40
20
20
0
0
10
20
30
40
50
60
70
80
-40
-15
10
35
60
85
LOAD CURRENT (mA)
TEMPERATURE (°C)
DROPOUT VOLTAGE
vs. LOAD CURRENT
DROPOUT vs. VOUT
OUTPUT VOLTAGE ACCURACY
vs. TEMPERATURE
DROPOUT (mV)
45
TA = -40°C
GUARANTEED MAXIMUM
120
100
80
MEAN
60
15
20
30
40
50
LOAD CURRENT (mA)
60
70
80
0.8
0.6
0.4
0.2
0
-0.2
-0.4
40
-0.6
20
-0.8
0
0
1.0
MAX8882/83 toc06
160
140
TA = +85°C
30
180
OUTPUT VOLTAGE (%)
60
200
MAX8882/3 toc04
TA = +25°C
75
10
120
SUPPLY VOLTAGE (V)
90
0
80mA LOAD, BOTH OUTPUTS
140
40
6
MAX8882/3 toc03
160
0
0
DROPOUT VOLTAGE (mV)
BOTH OUTPUTS LOADED
180
SUPPLY CURRENT (µA)
150
MAX8882/3 toc02
160
200
MAX8882/83 toc05
SUPPLY CURRENT (µA)
180
SUPPLY CURRENT (µA)
80mA LOAD, BOTH OUTPUTS
200
200
MAX8882/3 toc01
250
SUPPLY CURRENT
vs. TEMPERATURE
-1.0
2.5
2.7
2.9
VOUT (V)
3.1
3.3
-40
-25
-10
5
20
35
50
65
80
TEMPERATURE (°C)
_______________________________________________________________________________________
3
MAX8882/MAX8883
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics (continued)
(VOUT_ = 2.85V, IOUT_ = 80mA, VIN = +3.6V, COUT_ = 2.2µF, CBP = 0.01µF, and CIN = 2.2µF, unless otherwise noted.)
CHANNEL-TO-CHANNEL ISOLATION
vs. FREQUENCY
60
40
30
20
10
0
100Ω LOAD
100
80
60
THERMAL
COUPLING
40
CAPACITVE
COUPLING
20
0
0.01
0.1
1
10
100
1000
0.01
0.1
1
10
100
FREQUENCY (kHz)
FREQUENCY (kHz)
OUTPUT NOISE SPECTRAL DENSITY
vs. FREQUENCY
MAX8882 OUTPUT NOISE
(10Hz to 100kHz)
MAX8882/3 toc09
10000
1000
MAX8882/3 toc10
PSRR (dB)
50
120
MAX8882/3 toc08
100Ω LOAD
CHANNEL-TO-CHANNEL ISOLATION (dB)
70
MAX8882/3 toc07
PSRR vs. FREQUENCY
NOISE DENSITY (nV/√Hz)
MAX8882/MAX8883
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
1000
500µV/div
(AC-COUPLED)
VOUT_
100
10
0.01
0.1
1
10
100
1000
1ms/div
LOAD TRANSIENT
(VIN = 3.35V, ILOAD = 0 TO 80mA)
LINE TRANSIENT
MAX8882/3 toc11
MAX8882/3 toc12
4.5V
VIN
3.5V
20mV/div
(AC-COUPLED)
VOUT_
1V/div
20mV/div
(AC-COUPLED)
VOUT_
50mA/div
ILOAD
0
50µs/div
4
10µs/div
_______________________________________________________________________________________
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
LOAD TRANSIENT NEAR DROPOUT
SHUTDOWN RESPONSE
MAX8882/3 toc13
MAX8882/3 toc14
RLOAD = 100Ω
20mV/div
VOUT
OUTPUT
VOLTAGE
20V/div
0
VIN = VOUT + 0.1V
50µA/div
ILOAD
0
SHUTDOWN
VOLTAGE
1V/div
0
10µs/div
1ms/div
Pin Description
PIN
NAME
FUNCTION
1
OUTB
Regulator B Output. Sources up to 160mA continuous current. Bypass with a
2.2µF (<0.5Ω typ ESR) capacitor to GND (see the Capacitor Selection and
Regulator Stability section).
2
2
GND
Ground. This pin also functions as a heatsink. Solder to a large pad or the
circuit-board ground plane to maximize thermal dissipation.
3
—
BP
MAX8882
MAX8883
1
—
3
Reference Noise Bypass. Bypass with a low-leakage 0.01µF ceramic
capacitor for reduced noise at both outputs.
SHDNA
Shutdown A Input. A logic low shuts down regulator A. If SHDNA and
SHDNB are both low, both regulators and the reference turn off, and supply
current is reduced to 10nA. If either SHDNA or SHDNB is a logic high, the
reference is on. Connect to IN for normal operation.
—
4
SHDNB
Shutdown B Input. A logic low shuts down regulator B. If SHDNA and
SHDNB are both low, both regulators and the reference turn off, and supply
current is reduced to 10nA. If either SHDNA or SHDNB is a logic high, the
reference is on. Connect to IN for normal operation.
4
—
SHDN
Shutdown Input. A logic low shuts down both regulators and the reference,
reducing the entire supply current to 10nA. Connect to IN for normal
operation.
5
5
IN
Regulator Input. Supply voltage can range from +2.5V to +6.5V. This input
also supplies the on-chip reference. Bypass with 2.2µF to GND (see the
Capacitor Selection and Regulator Stability section).
6
6
OUTA
Regulator A Output. Sources up to 160mA continuous current. Bypass with
a 2.2µF (<0.5Ω typ ESR) capacitor to GND (see the Capacitor Selection and
Regulator Stability section).
_______________________________________________________________________________________
5
MAX8882/MAX8883
Typical Operating Characteristics (continued)
(VOUT_ = 2.85V, IOUT_ = 80mA, VIN = +3.6V, COUT_ = 2.2µF, CBP = 0.01µF, and CIN = 2.2µF, unless otherwise noted.)
The MAX8882/MAX8883 are low-noise, low-dropout,
low-quiescent-current linear regulators designed primarily for battery-powered applications. These parts are
available with preset output voltages ranging from 1.8V
to 3.3V, and the parts can supply loads up to 160mA.
Shutdown
MAX8882
The MAX8882 has a single shutdown control input
(SHDN). Drive SHDN low to shut down both outputs,
reducing supply current to 10nA. Connect SHDN to a
logic-high, or IN, for normal operation.
MAX8883
The MAX8883 has independent shutdown control
inputs (SHDNA and SHDNB). Drive SHDNA low to shut
down OUTA. Drive SHDNB low to shut down OUTB.
Drive both SHDNA and SHDNB low to shut down the
entire chip, reducing supply current to 10nA. Connect
both SHDNA and SHDNB to a logic-high, or IN, for normal operation.
Internal P-Channel Pass Transistor
The MAX8882/MAX8883 feature two 1Ω P-channel
MOSFET pass transistors. A P-channel MOSFET provides several advantages over similar designs using
PNP pass transistors, including longer battery life. It
requires no base drive, which reduces quiescent current significantly. PNP-based regulators waste considerable current in dropout when the pass transistor
saturates, and they also use high base-drive currents
under large loads. The MAX8882/MAX8883 do not suffer from these problems and only consume 165µA of
quiescent current whether in dropout, light-load, or
heavy-load applications (see the Typical Operating
Characteristics). While a PNP-based regulator has
dropout voltage that is independent of the load, a Pchannel MOSFET’s dropout voltage is proportional to
load current, providing for low dropout voltage at heavy
loads and extremely low dropout voltage at lighter
loads.
perature exceeds TJ = +160°C, the thermal sensor signals the shutdown logic, turning off the pass transistor
and allowing the IC to cool. The thermal sensor will turn
the pass transistor on again after the IC’s junction temperature cools by 10°C, resulting in a pulsed output
during continuous thermal-overload conditions.
Thermal-overload protection is designed to protect the
MAX8882/MAX8883 in the event of fault conditions. For
continual operation, do not exceed the absolute maximum junction-temperature rating of TJ = +150°C.
Operating Region and Power Dissipation
The MAX8882/MAX8883’s maximum power dissipation
depends on the thermal resistance of the case and circuit board, the temperature difference between the die
junction and ambient air, and the rate of air flow. The
power dissipation across the device is P = IOUT (VIN VOUT) (Figure 1). The maximum power dissipation is:
PMAX = (TJ - TA) / (TJB + TBA)
where TJ - TA is the temperature difference between
the MAX8882/MAX8883 die junction and the surrounding air, TJB (or TJC) is the thermal resistance of the
package, and TBA is the thermal resistance through the
printed circuit board, copper traces, and other materials to the surrounding air.
The GND pin of the MAX8882/MAX8883 performs the
dual functions of providing an electrical connection to
the ground and channeling heat away. Connect the
GND pin to ground using a large pad or ground plane.
SAFE OPERATING REGION
180
+70°C
160
140
120
+85°C
100
80
60
Current Limit
40
The MAX8882/MAX8883 contain two independent current limiters, one for each regulator, which monitor and
control the pass transistor’s gate voltage, limiting the
guaranteed maximum output current to 160mA minimum. The output can be shorted to ground for an indefinite time without damaging the part.
20
0
0
1
2
3
4
5
VIN - VOUT_ (V)
Figure 1. MAX8882/MAX8883 Safe Operating Region
Thermal-Overload Protection
Thermal-overload protection limits total power dissipation in the MAX8882/MAX8883. When the junction tem6
MAX8882/3 fig01
Detailed Description
IOUT_ (mA)
MAX8882/MAX8883
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
_______________________________________________________________________________________
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
Applications Information
Capacitor Selection and
Regulator Stability
Use a 2.2µF capacitor on the MAX8882/MAX8883 input
and a 2.2µF capacitor on the outputs. Larger input
capacitor values and lower ESRs provide better supplynoise rejection and line-transient response. To reduce
noise, improve load transients, and for loads up to
160mA, use larger output capacitors (up to 10µF). For
stable operation over the full temperature range and
with load currents up to 80mA, use 2.2µF.
Note that some ceramic dielectrics exhibit large capacitance and ESR variation with temperature. With
dielectrics such as Z5U and Y5V, it may be necessary
to use 4.7µF or more to ensure stability at temperatures
below -10°C. With X7R or X5R dielectrics, 2.2µF is sufficient at all operating temperatures. These regulators
are optimized for ceramic capacitors, and tantalum
capacitors are not recommended.
Use a 0.01µF bypass capacitor at BP (MAX8882) for
low output voltage noise. Increasing the capacitance
will slightly decrease the output noise, but increase the
startup time. (See the Shutdown Response graph in the
Typical Operating Characteristics.)
PSRR and Operation from Sources
Other than Batteries
The MAX8882/MAX8883 are designed to deliver low
dropout voltages and low quiescent currents in batterypowered systems. Power-supply rejection is 62dB at
low frequencies and rolls off above 100kHz. (See the
PSRR vs. Frequency graph in the Typical Operating
Characteristics.)
When operating from sources other than batteries,
improved supply-noise rejection and transient response
can be achieved by increasing the values of the input
and output bypass capacitors and through passive filtering techniques.
Dropout Voltage
A regulator’s minimum input-output voltage differential
(or dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this determines the useful end-of-life battery voltage. Because
the MAX8882/MAX8883 use a P-channel MOSFET pass
transistor, their dropout voltage is a function of drain-tosource on-resistance (RDS(ON)) multiplied by the load
current (see the Typical Operating Characteristics).
Chip Information
TRANSISTOR COUNT: 493
PROCESS: BiCMOS
Pin Configurations (continued)
TOP VIEW
OUTB 1
GND 2
MAX8883
SHDNA 3
6
OUTA
5
IN
4
SHDNB
SOT23-6
_______________________________________________________________________________________
7
MAX8882/MAX8883
Low-Noise Operation (MAX8882)
An external 0.01µF bypass capacitor at BP, in conjunction with an internal resistor, creates a lowpass filter.
The MAX8882 exhibits 40µVRMS of output voltage noise
with CBP = 0.01µF and COUT_ = 4.7µF. (See the Output
Noise Spectral Density graph in the Typical Operating
Characteristics.)
Dual, Low-Noise, Low-Dropout, 160mA Linear
Regulators in SOT23
6LSOT.EPS
MAX8882/MAX8883
Package Information
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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