19-1576; Rev 0; 10/99
150mA, Low-Dropout Linear Regulator
with Power-OK Output
General Description
The MAX8885 low-dropout (LDO) linear regulator operates
from a +2.5V to +6.5V input voltage range and delivers up
to 150mA. It uses a P-channel MOSFET pass transistor to
allow a low 85µA supply current—which is independent of
the load—as well as LDO voltage. The MAX8885 is opti-
mized to operate with low-cost, high-ESR output capaci-
tors such as small case-size tantalum capacitors. It is ideal
for cost-sensitive portable equipment such as PCS and
cellular phones. For a pin-compatible, functionally equiva-
lent device for use with a low-ESR, ceramic output capaci-
tor, refer to the MAX8875 data sheet.
The MAX8885 features a power-OK output that indicates
when the output is out of regulation, and is available in
preset output voltage versions of 5.0V, 3.3V, 3.0V, 2.7V,
and 2.5V. Other features include 1µA (max) shutdown cur-
rent, short-circuit protection, thermal shutdown protection,
and reverse-battery protection. The MAX8885 is available
in a miniature 5-pin SOT23 package.
o
Pin Compatible with MIC5206
o
Undervoltage Power-OK Output
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
o
Optimized for Low-Cost Tantalum Capacitors
MAX8885
Applications
PCS Phones
Cellular Phones
Cordless Phones
PCMCIA Cards
Modems
Hand-Held Instruments
Palmtop Computers
Electronic Planners
PART
MAX8885EUK25
MAX8885EUK27
MAX8885EUK30
MAX8885EUK33
MAX8885EUK50
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
MAX8885EUK25
MAX8885EUK27
MAX8885EUK30
MAX8885EUK33
V
OUT
(V)
2.5
2.7
3.0
3.3
TOP MARK
ADLE
ADLF
ADLG
ADLH
Note:
See Output Voltage Selector Guide for more information.
MAX8885EUK50
5.0
ADLJ
Note:
Other output voltages between 2.5V and 5.0V are avail-
able in 100mV increments—contact factory for information.
Minimum order quantity is 25,000 units.
Typical Operating Circuit
OUTPUT
PRESET
2.5V TO 5.0V
150mA
C
OUT
4.7µF
Pin Configuration
TOP VIEW
IN 1
5
OUT
INPUT
+2.5V TO +6.5V
IN
C
IN
1µF
OUT
GND 2
MAX8885
ON
OFF
MAX8885
100k
SHDN
GND
POK
TO
µC
SHDN 3
4
POK
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
MAX8885
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
= I
N
, 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
T
A
= -40°C to +85°C, I
OUT
= 100µA
T
A
= -40°C to +85°C,
I
OUT
= 100µA to 120mA
Maximum Output Current
Current Limit
Ground Pin Current
I
OUT
I
LIM
I
Q
I
OUT
= 100µA
I
OUT
= 150mA
I
OUT
= 100µA
Dropout Voltage (Note 2)
V
IN
-
V
OUT
∆V
LNR
∆V
LDR
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
I
OFF
V
IH
V
IL
I
SHDN
SHDN
= GND
V
IN
= 2.5V to 5.5V
V
SHDN
= 5.5V 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
IN
= (V
OUT
+ 0.1V) to 6.5V, I
OUT
= 1mA
I
OUT
= 100µA to 120mA, C
OUT
= 4.7µF
C
OUT
= 10µF, f = 10Hz to 100kHz
f = 100Hz
-0.15
CONDITIONS
MIN
2.5
-1
-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
2
2
mA
mA
µA
%
UNITS
V
2
_______________________________________________________________________________________
150mA, Low-Dropout Linear Regulator
with Power-OK Output
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
OUT(NOMINAL)
+ 1V,
SHDN
= I
N
, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
POWER-OK OUTPUT
(1 - V
OUT
/ V
OUT(NOMINAL)
)100, V
OUT
falling,
I
OUT
= 0
In dropout, V
OUT
falling
Hysteresis, I
OUT
= 0
POK Output Voltage Low
POK Output Leakage Current
THERMAL PROTECTION
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
T
SHDN
∆T
SHDN
170
20
°C
°C
V
OL
I
SINK
= 1mA
0
≤
V
POK
≤
6.5V, V
OUT
in regulation
-3
-5
-5.3
1
0.4
1
V
µA
-8
%
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX8885
Power-OK Voltage Threshold
V
POK
Note 1:
Limits are 100% production tested at T
A
= +25°C. Limits over the operating temperature range are guaranteed through cor-
relation 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
(MAX8885EUK30, V
IN
= +3.6V, C
IN
= 1µF, C
OUT
= 4.7µF,
SHDN
= IN, T
A
= +25°C, unless otherwise noted.)
GROUND PIN CURRENT
vs. INPUT VOLTAGE
MAX8885toc01
GROUND PIN CURRENT vs.
OUTPUT LOAD
MAX8885toc02
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
MAX8885EUK30
V
OUT
= 5.0V
MAX8885EUK50
MAX8885toc03
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)
_______________________________________________________________________________________
3
150mA, Low-Dropout Linear Regulator
with Power-OK Output
MAX8885
Typical Operating Characteristics (continued)
(MAX8885EUK30, V
IN
= +3.6V, C
IN
= 1µF, C
OUT
= 4.7µF,
SHDN
= IN, T
A
= +25°C, unless otherwise noted.)
GROUND PIN CURRENT
vs. TEMPERATURE
MAX8885toc04
OUTPUT VOLTAGE vs.
INPUT VOLTAGE
MAX8885toc05
OUTPUT VOLTAGE vs. OUTPUT LOAD
MAX8885toc06
130
120
GROUND PIN CURRENT (µA)
110
100
90
80
70
60
-40
-15
10
35
60
V
IN
= 3.6V
I
OUT
= 150mA
V
IN
= 3.6V OR 5.0V
I
OUT
= 0
V
IN
= 5.0V
I
OUT
= 150mA
3.5
3.0
OUTPUT VOLTAGE (V)
2.5
2.0
I
OUT
= 150mA
1.5
1.0
0.5
0
I
OUT
= 0
3.10
OUTPUT VOLTAGE (V)
3.05
3.00
V
IN
= 3.6V
2.95
V
IN
= 5.0V
2.90
0
1
2
3
4
5
6
0
INPUT VOLTAGE (V)
15 30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
85
TEMPERATURE (°C)
OUTPUT VOLTAGE vs. TEMPERATURE
MAX8885toc07
DROPOUT VOLTAGE vs.
OUTPUT LOAD
MAX8885toc08
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
60
55
R
OUT
= 60Ω
MAX8885toc09
130
120
OUTPUT VOLTAGE (V)
110
100
90
80
70
60
-40
-15
10
35
60
V
IN
= 5.0V
I
OUT
= 150mA
V
IN
= 3.6V
I
OUT
= 150mA
V
IN
= 3.6V OR 5.0V
I
OUT
= 0
250
65
200
DROPOUT VOLTAGE (mV)
T
A
= +85°C
50
PSRR (dB)
45
40
35
C
OUT
= 10µF
150
T
A
= +25°C
100
50
T
A
= -40°C
30
25
C
OUT
= 1µF
0.1
1
10
100
1000
FREQUENCY (kHz)
0
85
0
15 30 45 60 75 90 105 120 135 150
OUTPUT LOAD (mA)
TEMPERATURE (°C)
20
0.01
OUTPUT NOISE SPECTRAL DENSITY
vs. FREQUENCY
MAX8885toc10
OUTPUT NOISE (10Hz TO 100kHz)
MAX8885toc11
REGION OF STABLE C
OUT
ESR vs.
LOAD CURRENT
MAX8885toc12
10
OUTPUT NOISE SPECTRAL DENSITY (µV/Hz)
1000
100
V
OUT
500µV/div
C
OUT
= 1µF
0.1
1
C
OUT
= 10µF
0.01
I
OUT
= 50mA
0.1
1
10
FREQUENCY (kHz)
100
1000
C
OUT
= 10µF
I
LOAD
= 50mA
10ms/div
C
OUT
ESR (Ω)
1
10
STABLE REGION: C
OUT
= 4.7µF TO 10µF
0.1
1
30
60
90
120
150
LOAD CURRENT (mA)
4
_______________________________________________________________________________________
150mA, Low-Dropout Linear Regulator
with Power-OK Output
Typical Operating Characteristics (continued)
(MAX8885EUK30, V
IN
= +3.6V, C
IN
= 1µF, C
OUT
= 4.7µF,
SHDN
= I
N
, T
A
= +25°C, unless otherwise noted.)
LOAD-TRANSIENT RESPONSE
NEAR DROPOUT
MAX8885toc15
MAX8885
LINE-TRANSIENT RESPONSE
MAX8885toc13
LOAD-TRANSIENT RESPONSE
MAX8885toc14
5V
V
IN
4V
50mA
I
LOAD
25mA/div
0
50mA
I
LOAD
25mA/div
0
3.02V
V
OUT
3.00V
2.98V
R
OUT
= 60Ω
100µs/div
3.05V
V
OUT
25mV/div
3.05V
V
OUT
25mV/div
V
IN
= V
OUT
+ 0.1V
C
IN
= 1µF
5µs/div
3.0V
V
IN
= V
OUT
+ 0.5V
C
IN
= 1µF
5µs/div
3.0V
SHUTDOWN DELAY
MAX8885toc16
POK OUTPUT
MAX8885toc17
POK STARTUP RESPONSE
5V
V
OUT
2V/div
V
POK
2V/div
2.5V
0
2.5V
0
5V
V
IN
1V/div
2.5V
0
V
POK
2.5V/div
MAX8885toc18
3V
V
OUT
1V/div
0
2V
V
SHDN
1V/div
0
R
LOAD
= 60Ω
100µs/div
200µs/div
0
V
IN
2.5V/div
V
OUT
2.5V/div
0
4V
3V
2V
10ms/div
POK AND SHUTDOWN RESPONSE
MAX8885toc19
2V
0
2V
0
4V
2V
0
R
LOAD
= 60Ω
10µs/div
V
SHDN
V
OUT
V
POK
_______________________________________________________________________________________
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