_______________General Description
The MAX8873T/S/R and MAX8874T/S/R low-dropout lin-
ear regulators operate from a +2.5V to +6.5V input
range and deliver up to 120mA. A PMOS pass transis-
tor allows the low, 82A supply current to remain inde-
pendent of load, making these devices ideal for
battery-operated portable equipment such as cellular
phones and cordless phones.
The devices feature Dual ModeTM operation: their out-
put voltage is preset (at 3.15V for the T versions, 2.84V
for the S versions, or 2.80V for the R versions) or can be
adjusted with an external resistor divider. Total error on
the output is 3.5%. Output voltages are set on the low
side of popular ranges so that power drain is minimized
for longer battery life. Other features include low-power
shutdown, short-circuit protection, thermal shutdown
protection, and reverse battery protection. The
MAX8874 also includes an auto-discharge function,
which actively discharges the output voltage to ground
when the device is placed in shutdown mode. Both
devices come in a miniature 5-pin SOT23 package.
For dual versions, refer to the MAX8865/MAX8866 data
sheet. For low-noise versions with 30V
RMS
output
noise, refer to the MAX8877/MAX8878.
________________________Applications
Cordless Telephones
Modems
PCS Telephones
Hand-Held Instruments
Cellular Telephones
Palmtop Computers
PCMCIA Cards
Electronic Planners
____________________________Features
o
LP2980 Pin-Compatible SOT23 Package
o
Low, 55mV Dropout Voltage at 50mA I
OUT
(130mV at 120mA)
o
Low, 73A No-Load Supply Current
Low, 82A Operating Supply Current (even in
dropout)
o
Miniature External Components
o
Thermal Overload Protection
o
Output Current Limit
o
Reverse Battery Protection
o
Dual Mode Operation: Fixed or Adjustable
(1.25V to 6.5V) Output
o
Low-Power Shutdown
MAX8873T/S/R, MAX8874T/S/R
Low-Dropout, 120mA Linear Regulators
________________________________________________________________
Maxim Integrated Products
1
SOT23-5
TOP VIEW
GND
SET
SHDN
1
5 OUT
IN
MAX8873
MAX8874
2
3
4
__________________Pin Configuration
MAX8873
MAX8874
OUT
GND
SET
IN
SHDN
C
OUT
1F
C
IN
1F
BATTERY
OUTPUT
VOLTAGE
__________Typical Operating Circuit
19-1257; Rev 1; 3/98
PART
MAX8873
TEUK-T
MAX8873SEUK-T
MAX8874
TEUK-T
-40C to +85C
-40C to +85C
-40C to +85C
TEMP. RANGE
PIN-
PACKAGE
5 SOT23-5
5 SOT23-5
5 SOT23-5
______________Ordering Information
SOT TOP
MARK
ABZH
ABZI
ABZJ
MAX8874SEUK-T
-40C to +85C
5 SOT23-5
ABZK
Dual Mode is a trademark of Maxim Integrated Products.
MAX8873REUK-T
-40C to +85C
5 SOT23-5
ABZL
MAX8874REUK-T
-40C to +85C
5 SOT23-5
ABZM
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.
MAX8873T/S/R, MAX8874T/S/R
Low-Dropout, 120mA Linear Regulators
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
IN
= +3.6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
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.
V
IN
to GND ..................................................................-7V to +7V
Output Short-Circuit Duration ............................................Infinite
SET to GND ..............................................................-0.3V to +7V
SHDN to GND..............................................................-7V to +7V
SHDN to IN .................................................................-7V to 0.3V
OUT to GND ................................................-0.3V to (V
IN
+ 0.3V)
Continuous Power Dissipation (T
A
= +70C)
SOT23-5 (derate 7.1mW/C above +70C) .................571mW
Operating Temperature Range ...........................-40C to +85C
Junction Temperature ......................................................+150C
JA
..................................................................................140C/W
Storage Temperature Range .............................-65C to +160C
Lead Temperature (soldering, 10sec) .............................+300C
300
Shutdown Discharge
Resistance (MAX8874)
0.05
0
100
I
SHDN
SHDN Input Bias Current
V
0.4
V
IL
SHDN Input Threshold
2.0
V
IH
V
RMS
220
Output Voltage Noise
350
%/mA
0.011
0.030
%/V
-0.15
0
0.15
V
LNR
Line Regulation
mV
55
120
Dropout Voltage (Note 5)
V
2.5
6.5
V
IN
Input Voltage (Note 2)
1.1
A
73
150
I
Q
Ground Pin Current
3.05
3.15
3.25
V
OUT
Output Voltage
V
V
SET
6.5
V
OUT
Adjustable Output Voltage
Range (Note 3)
mA
120
Maximum Output Current
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
V
SHDN
= V
IN
C
OUT
= 100F
I
OUT
= 0mA
V
IN
= 2.5V to 6.5V, SET tied to OUT,
I
OUT
= 1mA
0mA
I
OUT
50mA,
SET = GND
I
OUT
= 50mA
CONDITIONS
mA
280
I
LIM
Current Limit (Note 4)
V
MAX887_T
10Hz to 1MHz
I
OUT
= 1mA
SET = GND
C
OUT
= 1F
MAX887_S
2.75
2.84
2.93
I
OUT
= 50mA
82
0.02
A
0.0001
1
I
Q
SHDN
Shutdown Supply Current
V
OUT
= 0V
T
A
= T
MAX
T
A
= +25C
T
A
= T
MAX
T
A
= +25C
nA
MAX887_R
2.70
2.80
2.88
I
OUT
= 0mA to 50mA
0.006
V
LDR
Load Regulation
SET tied to OUT
SET = GND
SHUTDOWN
MAX8873T/S/R, MAX8874T/S/R
Low-Dropout, 120mA Linear Regulators
_______________________________________________________________________________________
3
__________________________________________Typical Operating Characteristics
(V
IN
= +3.6V, C
IN
= 1F, C
OUT
= 1F, MAX887_T, T
A
= +25C, unless otherwise noted.)
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
CONDITIONS
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +3.6V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
Note 1:
Limits are 100% production tested at T
A
= +25C. Limits over the operating temperature range are guaranteed through cor-
relation using Statistical Quality Control (SQC) methods.
Note 2:
Guaranteed by line-regulation test.
Note 3:
Adjustable mode only.
Note 4:
For design purposes, the current limit should be considered 120mA minimum to 420mA maximum.
Note 5:
The 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
+ 2V.
T
SHDN
C
Thermal Shutdown Temperature
170
T
SHDN
C
Thermal Shutdown Hysteresis
20
SET Input Leakage Current
(Note 3)
nA
0.015
2.5
I
SET
V
SET
= 1.3V
SET Reference Voltage (Note 3)
V
1.225
1.25
1.275
V
SET
V
IN
= 2.5V to 6.5V,
IOUT = 1mA
SET INPUT
THERMAL PROTECTION
T
A
= +25C
T
A
= +25C
T
A
= T
MIN
to T
MAX
T
A
= T
MAX
0.5
1.215
1.25
1.285
3.00
3.05
3.10
3.15
3.20
3.25
3.30
0
20
60
100
120
OUTPUT VOLTAGE
vs. LOAD CURRENT
MAX8873/74-01
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
40
80
100
50
0
20
60
120
100
SUPPLY CURRENT
vs. LOAD CURRENT
60
90
MAX8873/74-02
LOAD CURRENT (mA)
SUPPLY CURRENT (
A
)
40
80
80
70
95
55
85
75
65
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0
1
2
4
6
7
OUTPUT VOLTAGE
vs. INPUT VOLTAGE
MAX8873/74-03
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
3
5
NO LOAD
MAX8873T/S/R, MAX8874T/S/R
Low-Dropout, 120mA Linear Regulators
4
_______________________________________________________________________________________
____________________________Typical Operating Characteristics (continued)
(V
IN
= +3.6V, C
IN
= 1F, C
OUT
= 1F, MAX887_T, T
A
= +25C, unless otherwise noted.)
1
10
MAX8873/74-08
FREQUENCY (kHz)
PSRR (dB)
70
60
50
40
30
20
10
0
100
1000
0.1
0.01
V
OUT
= 3.15V
R
L
= 100
C
OUT
= 10
F
C
OUT
= 1
F
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
10
0.01
0.1
10
100
1
1000
OUTPUT SPECTRAL NOISE DENSITY
vs. FREQUENCY
0.10
MAX8873/74-8A
FREQUENCY (kHz)
OUTPUT SPECTRAL NOISE DENSITY (
V/
Hz)
1
R
L
= 50
C
OUT
= 1F
C
OUT
= 100F
1000
0.01
0
60
80
20
40
100
120
REGION OF STABLE C
OUT
ESR
vs. LOAD CURRENT
0.1
MAX8873/74-8B
LOAD CURRENT (mA)
C
OUT
ESR (
)
1
10
100
INTERNAL FEEDBACK
STABLE REGION
C
OUT
= 1F
EXTERNAL FEEDBACK
0
20
40
60
80
100
120
140
160
0
20
60
100
120
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX8873/74-07
LOAD CURRENT (mA)
DROPOUT VOLTAGE (mV)
40
80
T
A
= +85C
T
A
= +25C
T
A
= -40C
I
LOAD
= 50mA, V
OUT
IS AC COUPLED
OUTPUT NOISE DC TO 1MHz
V
OUT
1ms/div
0
10
20
30
40
60
50
70
80
90
100
0
1
2
5
7
SUPPLY CURRENT
vs. INPUT VOLTAGE
MAX8873/74-04
INPUT VOLTAGE (V)
3
4
6
SUPPLY CURRENT (
A)
I
LOAD
= 0mA
I
LOAD
= 50mA
3.00
3.05
3.10
3.15
3.20
3.25
3.30
0
20
-20
60
100
OUTPUT VOLTAGE
vs. TEMPERATURE
MAX8873/74-05
TEMPERATURE (C)
OUTPUT VOLTAGE (V)
40
-40
80
I
LOAD
= 50mA
0
10
20
30
40
50
60
70
80
90
100
100
80
60
40
20
0
-20
-40
SUPPLY CURRENT
vs. TEMPERATURE
MAX8863/4-06
TEMPERATURE (C)
SUPPLY CURRENT (
A)
I
LOAD
= 50mA
MAX8873T/S/R, MAX8874T/S/R
Low-Dropout, 120mA Linear Regulators
_______________________________________________________________________________________
5
I
LOAD
= 0mA to 50mA, C
IN
= 10F, V
OUT
IS AC COUPLED
LOAD-TRANSIENT RESPONSE
3.16V
V
OUT
3.15V
3.14V
I
LOAD
50mA
0mA
10
s/div
V
IN
= V
OUT
+ 0.2V, I
LOAD
= 0mA to 50mA, C
IN
= 10F,
V
OUT
IS AC COUPLED
LOAD-TRANSIENT RESPONSE
I
LOAD
3.16V
V
OUT
3.15V
3.14V
50mA
0mA
10
s/div
____________________________Typical Operating Characteristics (continued)
(V
IN
= +3.6V, C
IN
= 1F, C
OUT
= 1F, MAX887_T, T
A
= +25C, unless otherwise noted.)
I
LOAD
= 50mA, V
OUT
IS AC COUPLED
LINE-TRANSIENT RESPONSE
3.16V
V
OUT
3.15V
3.14V
4.6V
3.6V
V
IN
50
s/div
V
IN
= V
OUT
+ 0.1V, I
LOAD
= 0mA to 50mA, C
IN
= 10F,
V
OUT
IS AC COUPLED
LOAD-TRANSIENT RESPONSE
0mA
50mA
10
s/div
3.16V
V
OUT
3.15V
3.14V
I
LOAD
NO LOAD
MAX8874 SHUTDOWN (NO LOAD)
0V
V
SHDN
4V
V
OUT
0V
2V
2V
500s/div
I
LOAD
= 50mA
MAX8874 SHUTDOWN
0V
V
SHDN
V
OUT
4V
2V
0V
2V
200s/div
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