19-1556; Rev 0; 10/99
150mA, Low-Dropout Linear Regulator
with Power-OK Output
General Description
The MAX8875 low-dropout linear regulator operates from
a +2.5V to +6.5V input range and delivers up to 150mA.
A P-channel MOSFET pass transistor allows its 85µA sup-
ply current to remain independent of the load, making this
device ideal for battery-operated portable equipment
such as PCS phones, cellular phones, cordless phones,
and modems.
The MAX8875 features a power-OK output that indicates
when the output is out of regulation. The device is avail-
able in several preset output voltage versions: 5.0V, 3.3V,
3.0V, 2.7V, or 2.5V. Other features include 1µA (max) shut-
down current, short-circuit protection, thermal shutdown
protection, and reverse-battery protection. The device
comes in a miniature 5-pin SOT23 package.
The MAX8875 is optimized for use with a 1µF ceramic out-
put capacitor. For a pin-compatible, functionally equivalent
device for use with a higher ESR output capacitor, see the
MAX8885 data sheet.
o
Power-OK Output
o
Small Output Capacitor (1µF ceramic)
o
Preset Output Voltages (±1% accuracy)
o
Guaranteed 150mA Output Current
o
85µA No-Load Supply Current
o
Low 110mV Dropout at 100mA Load (165mV at
150mA load)
o
Thermal-Overload and Short-Circuit Protection
o
Reverse-Battery Protection
o
60dB PSRR at 100Hz
o
1µA max Shutdown Current
Features
MAX8875
Applications
PCS Telephones
Cellular Telephones
Cordless Telephones
PCMCIA Cards
Hand-Held Instruments
Palmtop Computers
Electronic Planners
Modems
PART
MAX8875EUK25-T
MAX8875EUK27-T
MAX8875EUK30-T
MAX8875EUK33-T
MAX8875EUK50-T
Ordering Information
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
5 SOT23-5
5 SOT23-5
5 SOT23-5
5 SOT23-5
5 SOT23-5
Output Voltage Selector Guide
PART
MAX8875EUK25
MAX8875EUK27
MAX8875EUK30
MAX8875EUK33
V
OUT
(V)
2.5
2.7
3.0
3.3
TOP MARK
ADKZ
ADLA
ADLB
ADLC
Note:
See Output Voltage Selector Guide for more information.
MAX8875EUK50
5.0
ADLD
Note:
Other output voltages between 2.5V and 5.0V are avail-
able in 100mV increments—contact the factory for information.
Minimum order quantity is 25,000 units.
Typical Operating Circuit
OUTPUT
PRESET
2.5V TO 5.0V
150mA
C
OUT
1µF
Pin Configuration
TOP VIEW
IN
1
5
OUT
INPUT
+2.5V TO +6.5V
IN
C
IN
1µF
OUT
GND
2
MAX8875
ON
OFF
4
POK
MAX8875
100k
SHDN
GND
POK
TO
µC
SHDN
3
SOT23-5
________________________________________________________________
Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
150mA, Low-Dropout Linear Regulator
with Power-OK Output
MAX8875
ABSOLUTE MAXIMUM RATINGS
IN,
SHDN,
POK to GND...............................................-7V to +7V
SHDN
to IN ...............................................................-7V to +0.3V
OUT to GND ................................................-0.3V to (V
IN
+ 0.3V)
Output Short-Circuit Duration ........................................Indefinite
Continuous Power Dissipation (T
A
= +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C)..........571mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
θ
JA
...............................................................................+140°C/W
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
(V
IN
= V
OUT(NOMINAL)
+ 1V,
SHDN
= IN, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Input Voltage
SYMBOL
V
IN
T
A
= +25°C, I
OUT
= 100µA
Output Voltage Accuracy
I
OUT
= 100µA
T
A
= -40°C to +85°C
I
OUT
I
LIM
I
Q
I
OUT
= 100µA
I
OUT
= 150mA
I
OUT
= 100µA
Dropout Voltage (Note 2)
V
IN
- V
OUT
I
OUT
= 50mA
I
OUT
= 100mA
I
OUT
= 150mA
Line Regulation
Load Regulation
Output Voltage Noise
Output Voltage AC Power-
Supply Rejection Ratio
SHUTDOWN
Shutdown Supply Current
SHDN
Input Threshold
SHDN
Input Bias Current
POWER-OK OUTPUT
(1 - V
OUT
/ V
OUT(NOMINAL)
100, I
OUT
= 0,
V
OUT
falling
In dropout, V
OUT
falling
Hysteresis, I
OUT
= 0
-3
-5
-5.3
1
-8
%
I
OFF
V
IH
V
IL
I
SHDN
SHDN
= GND
V
IN
= 2.5V to 5.5V
SHDN
= IN or GND
T
A
= +25°C
T
A
= +85°C
T
A
= +25°C
T
A
= +85°C
2.0
0.4
0
0.05
100
0.005
0.02
1
µA
V
nA
PSRR
∆V
LNR
∆V
LDR
V
IN
= (V
OUT
+ 0.1V) to 6.5V, I
OUT
= 1mA
I
OUT
= 100µA to 120mA, C
OUT
= 1µF
C
OUT
= 10µF, f = 10Hz to 100kHz
f = 100Hz
-0.15
I
OUT
= 100µA to
120mA
CONDITIONS
MIN
2.5
-1.0
-2
-3
150
160
390
85
100
0.1
50
110
165
0
0.01
170
60
0.15
%/V
%/mA
µV
RMS
dB
220
mV
180
TYP
MAX
6.5
1.0
2
2
mA
mA
µA
%
UNITS
V
Maximum Output Current
Current Limit
Ground Pin Current
Power-OK Voltage Threshold
V
POK
2
_______________________________________________________________________________________
150mA, Low-Dropout Linear Regulator
with Power-OK Output
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
OUT(NOMINAL)
+ 1V,
SHDN
= IN, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
POK Output Voltage Low
POK Output Leakage Current
THERMAL PROTECTION
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
T
SHDN
∆T
SHDN
170
20
°C
°C
SYMBOL
V
OL
I
SINK
= 1mA
0
≤
V
POK
≤
6.5V, V
OUT
in regulation
CONDITIONS
MIN
TYP
MAX
0.4
1
UNITS
V
µA
MAX8875
Note 1:
Limits are 100% production tested at T
A
= +25°C. Limits over the operating temperature range are guaranteed through
correlation using Statistical Quality Control (SQC) methods.
Note 2:
Dropout voltage is defined as V
IN
- V
OUT
, when V
OUT
is 100mV below the value of V
OUT
for V
IN
= V
OUT
+ 0.5V.
Typical Operating Characteristics
(MAX8875EUK30, V
IN
= +3.6V, C
IN
= C
OUT
= 1µF,
SHDN
= IN, T
A
= +25°C, unless otherwise noted.)
GROUND PIN CURRENT vs.
INPUT VOLTAGE
MAX8875toc01
GROUND PIN CURRENT vs.
OUTPUT LOAD
MAX8875toc02
GROUND PIN CURRENT vs.
OUTPUT LOAD
V
IN
= V
OUT(NOMINAL)
+ 0.5V
115
GROUND PIN CURRENT (µA)
110
105
100
95
90
85
V
OUT
= 3.0V
MAX8875EUK30
V
OUT
= 5.0V
MAX8875EUK50
MAX8875toc03
MAX8875toc06
120
I
OUT
= 150mA
GROUND PIN CURRENT (µA)
100
80
60
40
20
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
I
OUT
= 0
115
110
V
IN
= 5.0V
105
100
V
IN
= 3.5V
95
90
85
0
120
GROUND PIN CURRENT (µA)
15 30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
0
15 30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
GROUND PIN CURRENT vs.
TEMPERATURE
130
120
GROUND PIN CURRENT (µA)
110
100
90
80
70
60
-40
-15
10
35
60
85
TEMPERATURE (°C)
V
IN
= 3.6V
I
OUT
= 150mA
V
IN
= 3.6V OR 5.0V
I
OUT
= 0
V
IN
= 5.0V
I
OUT
= 150mA
OUTPUT VOLTAGE vs.
INPUT VOLTAGE
MAX8875toc05
OUTPUT VOLTAGE vs. OUTPUT LOAD
3.10
3.5
3.0
OUTPUT VOLTAGE (V)
2.5
2.0
I
OUT
= 150mA
1.5
1.0
0.5
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
I
OUT
= 0
OUTPUT VOLTAGE (V)
3.05
3.00
V
IN
= 3.6V
2.95
V
IN
= 5.0V
2.90
0
15
30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
_______________________________________________________________________________________
3
150mA, Low-Dropout Linear Regulator
with Power-OK Output
MAX8875
Typical Operating Characteristics (continued)
(MAX8875EUK30, V
IN
= +3.6V, C
IN
= C
OUT
= 1µF,
SHDN
= IN, T
A
= +25°C, unless otherwise noted.)
DROPOUT VOLTAGE vs.
OUTPUT LOAD
MAX8875toc08
MAX8875toc07
OUTPUT VOLTAGE vs. TEMPERATURE
3.10
250
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX8875toc09
70
60
50
PSRR (dB)
OUTPUT VOLTAGE (V)
3.05
DROPOUT VOLTAGE (mV)
V
IN
= 3.6V OR 5.0V
I
OUT
= 0
200
150
C
OUT
= 10µF
T
A
= +85°C
T
A
= +25°C
40
30
C
OUT
= 1µF
20
T
A
= -40°C
3.00
V
IN
= 3.6V
I
OUT
= 150mA
2.95
V
IN
= 5.0V
I
OUT
= 150mA
-40
-15
10
35
60
85
TEMPERATURE (°C)
100
50
10
0
0.01
2.90
0
0
15
30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
0.1
1
10
100
1000
FREQUENCY (kHz)
OUTPUT NOISE SPECTRAL DENSITY
vs. FREQUENCY
OUTPUT NOISE SPECTRAL DENSITY (µV/√Hz)
MAX8875toc10
OUTPUT NOISE
MAX8875toc11
REGION OF STABLE C
OUT
ESR vs.
LOAD CURRENT
MAX8875toc12
10
C
OUT
= 10µF
I
OUT
= 50mA
100
f = 10Hz TO 100kHz
C
OUT
= 10µF
I
OUT
= 50mA
V
OUT
500µV/div
10
C
OUT
ESR (Ω)
1
C
OUT
= 10µF
1
C
OUT
= 1µF
STABLE REGION
0.1
0.1
0.01
0.1
1
10
100
10ms/div
FREQUENCY (kHz)
0.01
1
30
60
90
120
150
LOAD CURRENT (mA)
LINE-TRANSIENT RESPONSE
MAX8875toc13
LOAD-TRANSIENT RESPONSE
MAX8875toc14
LOAD-TRANSIENT RESPONSE
NEAR DROPOUT
MAX8875toc15
3.01V
V
OUT
3.00V
2.99V
V
IN
5V
4V
3.01V
V
OUT
I
LOAD
3.00V
2.99V
3.02V
V
OUT
3.00V
2.98V
10µs/div
I
OUT
= 50mA
I
LOAD
50mA
50mA
0
10µs/div
V
IN
= V
OUT
+ 0.5V, I
OUT
= 0 TO 50mA
0
10µs/div
V
IN
= V
OUT
+ 0.1V, I
OUT
= 0 TO 50mA
4
_______________________________________________________________________________________
150mA, Low-Dropout Linear Regulator
with Power-OK Output
Typical Operating Characteristics (continued)
(MAX8875EUK30, V
IN
= +3.6V, C
IN
= C
OUT
= 1µF,
SHDN
= IN, T
A
= +25°C, unless otherwise noted.)
MAX8875
SHUTDOWN DELAY
MAX8875toc16
POK OUTPUT
MAX8875toc17
3V
V
OUT
1V/div
0
2V
V
SHDN
1V/div
0
0
V
OUT
2V/div
V
POK
2V/div
0
4V
3V
2V
100µs/div
MAX8875EUK30, R
OUT
= 60Ω
R
POK
= 100kΩ
200µs/div
V
IN
1V/div
POK STARTUP RESPONSE
MAX8875toc18
POK AND SHUTDOWN RESPONSE
V
IN
2.5V/div
MAX8875toc19
5.0V
2V
0
V
SHDN
2V/div
0
2.5V
0
5.0V
V
POK
2.5V/div
0
10ms/div
R
POK
= 100kΩ
V
OUT
2.5V/div
2V
0
4V
V
OUT
2V/div
V
POK
2V/div
0
R
LOAD
= 60Ω
10µs/div
R
POK
= 100kΩ
Pin Description
PIN
1
2
3
4
5
NAME
IN
GND
SHDN
POK
OUT
FUNCTION
Regulator Input. Supply voltage can range from 2.5V to 6.5V. Bypass with 1µF to GND (see the
Capacitor
Selection and Regulator Stability
section).
Ground. This pin also functions as a heatsink. Solder to a large pad or the circuit-board ground plane to
maximize power dissipation.
Active-Low Shutdown Input. A logic low reduces the supply current to below 1µA. Connect to IN for normal
operation.
Power-OK Output. Active-low, open-drain output indicates an out-of-regulation condition. Connect a 100k
pull-up resistor to OUT for logic levels. If not used, leave this pin unconnected.
Regulator Output. Fixed 5.0V, 3.3V, 3.0V, 2.7V, or 2.5V output. Sources up to 150mA. Bypass with 1µF
(<0.2Ω typical ESR) ceramic capacitor to GND.
_______________________________________________________________________________________
5
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