19-0516; Rev 1; 9/08
KIT
ATION
EVALU
BLE
AVAILA
Dual 300mA Pin-Programmable LDO
Linear Regulators
General Description
Features
♦
Pin-Programmable Output Voltages
♦
300mA Output Current
♦
Low 90mV Dropout at 100mA Load
♦
Open-Drain, Active-Low
RESET
(MAX8633)
♦
Low 45µV
RMS
Output Noise (MAX8634/MAX8636)
♦
Low 54µA Quiescent Supply Current
♦
Low < 1µA Maximum Shutdown Current
♦
Output Current Limit
♦
Thermal Shutdown
MAX8633–MAX8636
The MAX8633–MAX8636 offer low-dropout (LDO) volt-
age and ultra-low-power regulation in a subminiaturized
2mm x 2mm µDFN package. The devices operate from
a 2.7V to 5.5V supply and deliver up to 300mA from
each output, with a typical dropout voltage of 90mV at
100mA load current. Each device is designed with
internal p-channel MOSFET pass transistors to ensure a
low-quiescent supply current of 54µA (typical, both
LDOs on). Other features include low-noise operation
(MAX8634/MAX8636), output current limiting, and ther-
mal shutdown.
The MAX8633 features an open-drain, active-low
RESET
output to monitor OUT2, eliminating external
components and adjustments. The MAX8633 asserts a
RESET
signal (120ms minimum timeout) when VOUT2
drops below 87% of the nominal output voltage. The
MAX8634/MAX8636 feature a noise bypass input to the
internal reference for low output noise (45µV
RMS
typ).
The MAX8634/MAX8635 provide independent
SHDN
inputs for disabling the regulators, while the MAX8633/
MAX8636 provide a single
SHDN
input for disabling
both regulators.
The MAX8633/MAX8635/MAX8636 have two logic
inputs that select one of nine preset output-voltage
combinations, eliminating external 1% resistors, as well
as inventory burden. The MAX8634 has one logic input
to select three output-voltage options.
The MAX8633–MAX8636 are available in an 8-pin, 2mm
x 2mm µDFN package for minimizing footprint, and an
8-pin, 3mm x 3mm TDFN package for higher power dis-
sipation. The devices are specified over the extended
temperature range (-40°C to +85°C). All packages are
lead free.
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
8 µDFN
2mm x 2mm
8 TDFN
3mm x 3mm
8 µDFN
2mm x 2mm
TOP
MARK
AAH
AOQ
AAI
MAX8633ELA+
-40°C to +85°C
MAX8633ETA+ -40°C to +85°C
MAX8634ELA+
-40°C to +85°C
+Denotes
a lead-free/RoHS-compliant package.
Ordering Information continued at end of data sheet.
Typical Operating Circuits
INPUT
2.7V TO 5.5V
IN
C
IN
2.2μF
OUT1
C
OUT1
2.2μF
Applications
Cellular and Cordless Phones
PDAs and Digital Cameras
Small LCD Displays
Notebook Computers
Wireless LAN Cards
Handheld Instruments
MAX8633
OUT2
P1
P2
SHDN
GND
RESET
C
OUT2
2.2μF OUT2
Pin Configurations and Selector Guide appear at end of
data sheet.
Typical Operating Circuits continued at end of data sheet.
1
________________________________________________________________
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.
Dual 300mA Pin-Programmable LDO
Linear Regulators
MAX8633–MAX8636
ABSOLUTE MAXIMUM RATINGS
(All voltages refer to GND, unless otherwise noted.)
IN ...........................................................................-0.3V to +6.0V
SHDN, SHDN1, SHDN2, RESET,
P, P1, P2, BP, OUT1, OUT2 .....................-0.3V to (V
IN
+ 0.3V)
Continuous Output Short-Circuit Duration..................Continuous
Continuous Power Dissipation (T
A
= +70°C)
8-Pin µDFN 2mm x 2mm
(derate 4.8mW/°C above +70°C) .................................380mW
8-Pin TDFN 3mm x 3mm
(derate 23.8mW/°C above +70°C) .............................1904mW
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
(V
IN
= 3.7V,
SHDN
=
SHDN1
=
SHDN2
= IN, P = P1 = P2 = GND, CIN = 2.2µF, C
OUT1
= 2.2µF, C
OUT2
= 2.2µF, CBP = 0.01µF, T
A
=
-40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Input Voltage
Input Undervoltage
Lockout
Ground Current
Shutdown Supply
Current
OUT1, OUT2
I
OUT_
= 70mA; T
A
= +25°C
Output Voltage
Accuracy (for Any
Output Voltage)
Current Limit
Drop-Out Voltage
I
LIM
V
IN
- V
OUT
I
OUT_
= 70mA
I
OUT_
= 0.1mA to 300mA; V
IN
= (V
OUT_
+ 0.5V) to
5.5V
OUT_ = 0V
V
OUT_
= 2.8V (MAX8633);
V
OUT_
= 2.85V (MAX8634/MAX8635/MAX8636);
I
OUT_
= 100mA (Note 2)
MAX8633
MAX8635
MAX8634
MAX8636
f < 1kHz
PSRR
I
OUT_
= 30mA
f < 10kHz
55
-0.7
-1
-1.8
400
500
90
+0.7
+1
+1.7
600
200
mA
mV
%
SYMBOL
V
IN
V
UVLO
V
IN
rising; hysteresis = 95mV (typ)
I
OUT_
= 0mA
I
Q
I
OUT_
= 100mA
I
OUT_
= 10mA, dropout (Note 2)
I
OFF
SHDN_
= GND
T
A
= +25°C
T
A
= +85°C
CONDITIONS
MIN
2.7
2.15
2.25
54
60
60
0.005
0.01
1
µA
TYP
MAX
5.5
2.35
75
µA
UNITS
V
V
450
µV
RMS
45
60
dB
Output Noise
f = 10Hz to 100kHz;
I
OUT_
= 10mA
Output AC Power-
Supply Rejection
Ratio
2
_______________________________________________________________________________________
Dual 300mA Pin-Programmable LDO
Linear Regulators
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 3.7V,
SHDN
=
SHDN1
=
SHDN2
= IN, P = P1 = P2 = GND, CIN = 2.2µF, C
OUT1
= 2.2µF, C
OUT2
= 2.2µF, CBP = 0.01µF, T
A
=
-40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
Input Voltage High
Input Voltage Low
Input Bias Current
Turn-On Delay
TRI-LEVEL INPUTS (P, P1, P2)
Termination
Resistance to IN or
GND for Setting High,
Open, and Low States
Input Load
Capacitance for
Open State
RESET
RESET
High
Threshold
RESET
Threshold
Hysteresis
RESET
Output
Voltage Low
RESET
Output High
Leakage Current
RESET
Delay
THERMAL PROTECTION
Thermal-Shutdown
Threshold
Thermal-Shutdown
Hysteresis
T
SHDN
ΔT
SHDN
+165
15
°C
°C
I
LEAK
t
RP
Percent of nominal OUT2; OUT2 rising
Percent of nominal OUT2; OUT2 falling
I
RESET
= 20µA; V
IN
= 1.0V
I
RESET
= 500µA; V
IN
= 3.7V
V
RESET
= V
IN
= 5.5V
T
A
= +25°C
T
A
= +85°C
120
84
87
4.5
10
5
0.1
1
150
180
100
100
300
90
%
%
mV
nA
ms
For high or low state
IN = 2.7 to 5.5V
For open state
100
1
kΩ
SYMBOL
V
IH
V
IL
I
SHDN_
V
IN
= 2.7V to 5.5V
V
IN
= 2.7V to 5.5V
V
IN
= 2.7V to 5.5V;
V
SHDN_
= GND or IN
T
A
= +25°C
T
A
= +85°C
0.1
1
90
CONDITIONS
MIN
1.5
0.5
1000
TYP
MAX
UNITS
SHUTDOWN INPUTS (SHDN,
SHDN1,
AND
SHDN2)
V
nA
µs
MAX8633–MAX8636
From
SHDN
= high to 87% of V
OUT_
;
I
OUT_
= 70mA
Design guide only
50
pF
From OUT2 rising to
RESET
rising
Note 1:
All units are 100% tested at T
A
= +25°C. Limits over the operating temperature range are guaranteed by design.
Note 2:
The dropout voltage is defined as V
IN
- V
OUT_
when V
OUT_
drops by 100mV from V
OUT_
when measured at V
IN
= +3.7V.
Note 3:
Connect P_ to IN or GND through a resistor less than 1kΩ.
_______________________________________________________________________________________
3
Dual 300mA Pin-Programmable LDO
Linear Regulators
MAX8633–MAX8636
Typical Operating Characteristics
(V
IN
= 3.8V, P = P1 = P2 = GND, I
OUT1, 2
= 70mA, C
OUT1
= 2.2µF, C
OUT2
= 2.2µF, C
BP
= 0.01µF, C
IN
= 2.2µF, and T
A
= +25°C,
unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
(MAX8633ELA+)
MAX8633 toc01
SUPPLY CURRENT vs. LOAD CURRENT
(MAX8635ELA+)
MAX8633 toc02
SUPPLY CURRENT vs. TEMPERATURE
(MAX8633ELA+)
I
OUT1
= I
OUT2
= 70mA
MAX8633 toc03
70
I
OUT1
= I
OUT2
= 70mA
60
SUPPLY CURRENT (μA)
50
40
30
20
10
I
OUT1
= I
OUT2
= 0mA
70
70
65
SUPPLY CURRENT (μA)
60
55
I
OUT1
= I
OUT2
= 0mA
50
45
SUPPLY CURRENT (μA)
65
60
55
P1 = P2 = IN
0
0
1
2
3
4
5
6
SUPPLY VOLTAGE (V)
50
0
50
100
150
200
250
300
LOAD CURRENT (mA)
40
-40
-15
10
35
60
85
TEMPERATURE (°C)
DROPOUT VOLTAGE vs. LOAD CURRENT
(MAX8633ELA+)
MAX8633 toc04
DROPOUT VOLTAGE vs. OUT1 VOLTAGE
(MAX8633ELA+)
MAX8633 toc05
OUTPUT VOLTAGE ACCURACY
vs. TEMPERATURE (MAX8633ELA+)
1.5
OUT1 VOLTAGE ACCURACY (%)
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
-40
-15
10
35
60
85
OUT1
MAX8633 toc06
0.30
0.25
DROPOUT VOLTAGE (V)
0.20
0.15
0.10
0.05
OUT1
0
0
50
100
150
200
250
80
2.0
DROPOUT VOLTAGE (mV)
70
60
50
OUT1
P1 = P2 = IN
40
2.60
2.65
2.70 2.75
2.80 2.85
OUT1 VOLTAGE (V)
2.90 2.95
300
LOAD CURRENT (mA)
TEMPERATURE (°C)
PSRR vs. FREQUENCY
(MAX8636ELA+)
MAX8633 toc07
CHANNEL-TO-CHANNEL ISOLATION
vs. FREQUENCY (MAX8636ELA+)
MAX8633 toc08
OUTPUT SPECTRAL NOISE DENSITY
vs. FREQUENCY (MAX8636ELA+)
OUT1
P1 = IN
P2 = GND
MAX8633 toc09
70
60
50
PSRR (dB)
40
30
20
10
0
R
OUT1
= 100Ω
P1 = IN
P2 = GND
0.01
0.1
1
FREQUENCY (kHz)
10
70
60
50
PSRR (dB)
40
30
20
10
R
OUT1
= 100Ω
0
10,000
NOISE DENSITY (nV/ Hz)
1000
100
10
0.01
0.1
1
FREQUENCY (kHz)
10
100
0.01
0.1
1
10
100
1000
FREQUENCY (kHz)
100
4
_______________________________________________________________________________________
Dual 300mA Pin-Programmable LDO
Linear Regulators
Typical Operating Characteristics (continued)
(V
IN
= 3.8V, P = P1 = P2 = GND, I
OUT1, 2
= 70mA, C
OUT1
= 2.2µF, C
OUT2
= 2.2µF, C
BP
= 0.01µF, C
IN
= 2.2µF, and T
A
= +25°C,
unless otherwise noted.)
OUTPUT NOISE DC TO 100kHz
(MAX8636ELA+)
MAX8633 toc10
MAX8633–MAX8636
LINE TRANSIENT RESPONSE
(MAX8633ELA+)
MAX8633 toc11
4.8V
V
IN
3.8V
1V/div
0
50μV/div
AC
V
OUT1
MAX8633
I
OUT1
= 70mA
1ms/div
40μs/div
10mV/div
LOAD TRANSIENT
(MAX8633ELA+ OUT1 ILOAD = 1mA TO 70mA)
MAX8633 toc12
LOAD TRANSIENT NEAR DROPOUT
(V
IN
= V
OUT
+ 0.1V, MAX8633ELA+ OUT1)
MAX8633 toc13
70mA
I
OUT1
1mA
100mA/div
0
I
OUT1
1mA
70mA
100mA/div
0
AC
V
OUT1
MAX8633
V
IN
= 3.8V
40μs/div
20mV/div
AC
V
OUT1
MAX8633
V
IN
= V
OUT1
+ 0.1V
40μs/div
20mV/div
RESET TIMING
(MAX8633ELA+)
MAX8633 toc14
OUT1 AND OUT2 TURN-ON SEQUENCE
(MAX8633ELA+)
MAX8633 toc15
EXITING SHUTDOWN
(MAX8634ELA+)
MAX8633 toc16
SHDN
OUT1
5V/div SHDN
0
2V/div
0
OUT1
MAX8633
P1 = P2 = GND
I
OUT1
= I
OUT2
= 70mA
2V/div
0
2V/div
0
SHDN1
0
2V/div
2V/div
OUT1
RESET
SHDN2
0
2V/div
2V/div
0
MAX8633
OUT2
2V/div
0
40μs/div
OUT2
2V/div
MAX8634
P = IN
R
OUT1
= R
OUT2
= 100Ω
40μs/div
40ms/div
_______________________________________________________________________________________
5
