19-1889; Rev 3; 3/04
150mA, SOT23, Low-Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
MAX6329/MAX6349
General Description
The MAX6329/MAX6349 are low-dropout, micropower
linear voltage regulators with integrated microproces-
sor reset circuits. Each is available with preset +3.3V,
+2.5V, +1.8V, or adjustable output voltages and can
deliver up to 150mA load current. Employing internal P-
channel MOSFET pass transistors, the devices con-
sume only 25µA supply current, independent of the
device load. The low supply current, low dropout volt-
age, and integrated reset functionality make these
devices ideal for battery powered portable equipment.
The MAX6329/MAX6349 include an internal reset circuit
that indicates when the regulator output drops below
standard microprocessor supply tolerances (-5% or
-10%). The reset output remains asserted for 100ms
(min) after the regulator output exceeds the selected
reset threshold, ensuring that supply voltages and clock
oscillators have stabilized before processor activity is
enabled. Reset outputs are available in push-pull (active-
low or -high) and open-drain (active-low) options. The
internal reset circuit replaces external microprocessor
supervisors or RC-based reset time delays.
The MAX6329/MAX6349 are optimized for use with a
1µF (min) output capacitor. The regulator output volt-
age is adjustable with an external resistor-divider net-
work at SET (reset threshold voltages track the desired
output voltage). Each device includes thermal shut-
down protection, output short-circuit protection, and
reverse leakage protection. The MAX6329 includes a
shutdown feature to reduce regulator current below
1µA (max) and the MAX6349 offers a manual reset
input to assert a microprocessor reset while the regula-
tor output is within specification.
Features
o
Preset +3.3V/+2.5V/+1.8V or Adjustable Regulator
Output
o
±3.0% Regulator Accuracy Over the Specifed
Operating Range
o
25µA Supply Current
o
Low 180mV Dropout at 100mA Load
o
Small Output Capacitor (1µF min ceramic or
tantalum)
o
Zero Reverse Leakage Current
o
Thermal and Short-Circuit Protection
o
Integrated Microprocessor Reset Circuit with
100ms (min) Timeout
o
Open-Drain and Push-Pull Reset Outputs
o
Regulator Shutdown Input (MAX6329) or Manual
Reset Input (MAX6349)
o
6-Pin SOT23 Package
Ordering Information
PART
MAX6329_
_ UT-T
MAX6349_
_ UT-T
TEMP RANGE
0°C to +85°C
0°C to +85°C
PIN-
PACKAGE
6 SOT23-6
6 SOT23-6
________________________Applications
Hand-Held Instruments
Electronic Planners
Palm Top Computers
PCMCIA Cards
USB Devices
Cellular Telephones
Cordless Telephones
Modems
These parts offer a choice of regulator/reset voltages and reset
outputs. From the Selector Guide, insert the desired suffix let-
ters into the blanks to complete the part number. Each device
is available in nine standard versions. Sample stock is general-
ly held on standard versions only (see Standard Versions
table). Standard versions have an order increment requirement
of 2500 pieces. Nonstandard versions have an order increment
requirement of 10,000 pieces. Contact factory for availability of
nonstandard versions.
Pin Configuration
TOP VIEW
IN
1
6
OUT
GND
2
MAX6329/
MAX6349
5
SET
Selector Guide appears at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
(MR) SHDN
3
4
RESET/RESET
SOT23-6
( ) ARE FOR MAX6349 ONLY.
________________________________________________________________
Maxim Integrated Products
1
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.
150mA, SOT23, Low Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
MAX6329/MAX6349
ABSOLUTE MAXIMUM RATINGS
IN to GND .................................................................-0.3V to +7V
SHDN
to GND...........................................................-0.3V to +7V
SET to GND ..............................................-0.3V to (V
OUT
+ 0.3V)
MR
to GND ...............................................................-0.3V to +7V
RESET,
RESET
to GND, (Push-Pull) ..........0.3V to (V
OUT
+ 0.3V)
RESET
to GNd,(Open-Drain).....................-0.3V to (V
OUT
+0.3V)
OUT to GND .............................................................-0.3V to +7V
Short-Circuit Duration.................................................Continuous
Maximum Current into Any Pin (except IN, OUT) ............±20mA
Continuous Power Dissipation (T
A
= +70°C)
6-Pin SOT23 (derate 7.1mW/°C above +70°C).............571mW
Thermal Resistance (θ
JA
) ............................................+140°C/W
Operating Temperature Range...............................0°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
= +3.6V, T
A
= 0°C to +85°C. Typical values are at I
OUT
= 0, C
OUT
= 2.2µF, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Input Voltage Range
Supply Current
Shutdown Supply Current
REGULATOR
Maximum Output Current
V
IN
= 4.0V to 5.5V, SET = GND, I
OUT
= 0 to
100mA, T/S Versions
Output Voltage (Note 2)
V
OUT
V
IN
= 3.0V to 5.5V, SET = GND, I
OUT
= 0 to
100mA, Z/Y Versions
V
IN
= 2.5V to 5.5V, SET = GND, I
OUT
= 0 to
100mA, W/V Versions
I
LOAD
= 10mA, T/S Versions
I
LOAD
= 150mA, T/S Versions
Dropout Voltage (Note 3)
∆V
DO
I
LOAD
= 10mA, Z/Y Versions
I
LOAD
= 150mA, Z/Y Versions
I
LOAD
= 10mA, W/V Versions
I
LOAD
= 150mA, W/V Versions
Output Current Limit
Input Reverse Leakage Current
Startup-Time Response
SHDN
Input Voltage
SHDN
Input Current
SET Reference Voltage
SET Input Leakage Current
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
V
IL
V
IH
I
SHDN
V
SET
I
SET
V
IN
= V
OUT
+1V
V
IN
= 0, V
OUT
= 5.5V
Rising edge of V
IN
or
SHDN
to V
OUT
R
L
= 68Ω, SET = GND, C
L
= 1µF
MAX6329 only
SHDN
= GND or IN MAX6329 only
0.8
✕
V
IN
-1
1.20
-10
160
20
0.1
1.23
1
1.26
+10
150
3.20
2.425
1.745
3.3
2.5
1.8
20
300
25
300
60
600
350
0.01
500
0.3
✕
V
IN
1.5
3.40
2.575
1.855
30
360
35
400
200
750
mA
µA
µs
V
µA
V
nA
o
o
SYMBOL
V
IN
I
Q
At GND
T
A
= +25 C
o
CONDITIONS
MIN
2.5
TYP
25
MAX
5.5
50
1
UNITS
V
µA
µA
mA
V
mV
C
C
2
_______________________________________________________________________________________
150mA, SOT23, Low Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +3.6V, T
A
= -0°C to +85°C. Typical values are at I
OUT
= 0, C
OUT
= 2.2µF, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
RESET CIRCUIT
MAX63_9T SET = GND
MAX63_9S SET = GND
MAX63_9Z SET = GND
Reset Threshold (Note 2)
V
TH
MAX63_9Y SET = GND
MAX63_9W SET = GND
MAX63_9V SET = GND
MAX63_9T/Z/W SET = divider, Figure 1 (Note 4)
MAX63_9S/Y/V SET = divider, Figure 1 (Note 4)
Reset Timeout Period
V
OUT
to Reset Delay
MR
Input Voltage
MR
Minimum Input Pulse
MR
Glitch Rejection
MR
to Reset Delay
MR
Pullup Resistance
Open-Drain
RESET
Output
Voltage
Open-Drain Reset Output
Leakage Current
Push-Pull
RESET
Output Voltage
V
OL
I
LKG
V
OL
V
OH
Push-Pull RESET Output Voltage
V
OL
V
OH
V
OUT
≥
1.0V, I
SINK
= 50µA
V
OUT
< V
TH
(min), I
SINK
= 3.2mA
V
OUT
> V
TH
(max), I
SOURCE
= 500µA
V
OUT
> V
TH
(max), I
SINK
= 3.2mA
V
OUT
< V
TH
, I
SOURCE
= 150µA
0.8
✕
V
OUT
0.8
✕
V
OUT
0.4
V
t
RP
t
RD
V
IL
V
IH
MAX6349 only
MAX6349 only
MAX6349 only
MAX6349 only
MAX6349 only
V
OUT
> 1.0V, I
SINK
= 50µA
V
OUT
> 2.7V, I
SINK
= 3.2mA
10
0.8
✕
V
OUT
1
120
500
20
50
0.3
0.4
1.0
0.3
0.4
V
2.92
2.75
2.21
2.08
1.59
1.50
3.185
3.02
2.41
2.28
1.74
1.65
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6329/MAX6349
0.885
✕
V
ADJ
0.965
✕
V
ADJ
0.835
✕
V
ADJ
0.915
✕
V
ADJ
100
200
35
0.2
✕
V
OUT
300
ms
µs
V
µs
ns
ns
kΩ
V
µA
Note 1:
Limits over temperature are guaranteed by design and not production tested.
Note 2:
Specification from 0°C to less than 25°C is guaranteed to four sigma only.
Note 3:
Dropout voltage is defined as V
IN
- V
OUT
when V
OUT
is 2% below the value of V
OUT
for V
IN
= V
OUT
+ 1V.
Note 4:
V
ADJ
= VSET(1 + R1/R2), where VSET = 1.23V nominal.
_______________________________________________________________________________________
3
150mA, SOT23, Low Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
MAX6329/MAX6349
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
GROUND PIN CURRENT
vs. INPUT VOLTAGE
MAX6329/49 toc01
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX6329/49 toc02
MAXIMUM PULSE DURATION
vs. RESET THRESHOLD OVERDRIVE
MAX6329/49 toc03
40
35
GROUND PIN CURRENT (µA)
30
25
20
15
10
5
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
I
OUT
= 150mA
11
10
SHUTDOWN CURRENT (nA)
9
8
7
6
5
4
3
2
1
0
2.5
3.0
3.5
4.0
4.5
5.0
250
200
PULSE DURATION (µs)
I
OUT
= 0
150
RESET ASSERTS ABOVE
THIS LINE
100
50
0
5.5
1
10
100
INPUT VOLTAGE (V)
RESET THRESHOLD OVERDRIVE (V
TH
- V
OUT
) (mV)
DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX6329/49 toc04
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX6329/49 toc05
OUTPUT VOLTAGE vs. INPUT VOLTAGE
MAX6329/49 toc06
300
250
DROPOUT VOLTAGE (mV)
200
0
-10
-20
PSRR (dB)
-30
-40
-50
3.5
3.0
OUTPUT VOLTAGE (V)
2.5
2.0
1.5
1.0
0.5
150
100
50
V
OUT
= 3.3V
0
0
30
60
90
120
150
LOAD CURRENT (mA)
C
OUT
= 1µF
-60
0.01
0.1
1
10
FREQUENCY (kHz)
0
0
1
2
3
4
MAX63_9S/T
5
6
INPUT VOLTAGE (V)
REGION OF STABLE C
OUT
ESR
vs. LOAD CURRENT
MAX6329/49 toc07
OUTPUT NOISE
MAX6329/49 toc08
SHUTDOWN RESPONSE
MAX6329/49 toc09
150
125
100
75
50
25
STABLE REGION
0
0
C
OUT
= 4.7µF
SHDN
5V/div
C
OUT
ESR (Ω)
V
OUT
10mV/div
OUT
5V/div
RESET
5V/div
C
OUT
= 1µF
10ms/div
50ms/div
15 30 45 60 75 90 105 120 135 150
LOAD CURRENT (mA)
4
_______________________________________________________________________________________
150mA, SOT23, Low Dropout Linear Regulators
with Internal Microprocessor Reset Circuit
MAX6329/MAX6349
Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted.)
STARTUP RESPONSE
MAX6329/49 toc10
LOAD TRANSIENT RESPONSE
MAX6329/49 toc11
V
IN
5V/div
V
OUT
50mV/div
V
OUT
2V/div
I
OUT
= 50mA
C
OUT
= 1µF
20µs/div
200µs/div
V
IN
= 5V
I
OUT
= 0 - 100mA
LOAD TRANSIENT RESPONSE
NEAR DROPOUT
LINE TRANSIENT
MAX6329/49 toc13
MAX6329/49 toc12
5V
V
IN
4.5V
V
OUT
50mV/div
V
OUT
50mV/div
V
IN
= 3.6V
I
OUT
= 0 - 100mA
200µs/div
500µs/div
V
IN
= 3.6V
I
OUT
= 0 - 100mA
50mA
_______________________________________________________________________________________
5