General Description
The MAX4834/MAX4835 family of low-dropout (LDO)
linear regulators feature an accurate current-limiting
switch with an integrated FLAG or RESET function. These
devices operate from 2.5V to 5.5V and deliver up to
250mA of load current at a preset output voltage. Preset
output voltage levels are 1.8V/2.5V/2.8V/3.0V/3.3V.
The MAX4834/MAX4835 offer a programmable soft-
start control function to eliminate false reset during
startup. The MAX4834 provides a FLAG function to noti-
fy the system when the load current exceeds the limit.
The MAX4835 provides a RESET function to notify the
system when the output drops below the threshold.
Additionally, reverse-current protection prevents cur-
rent flowing from the output to the input. Other features
include a low 90µA quiescent current, a 0.1µA shut-
down current.
The MAX4834/MAX4835 are available in space-saving
6-pin SOT23 and TDFN packages. Each device is speci-
fied over the -40°C to +85°C extended temperature
range. Contact factory for other programmed output volt-
age versions from 1.5V to 3.3V in 100mV increments.
For pin-compatible 100mA versions of this device, refer
to the MAX4832/MAX4833. For pin-compatible 500mA
versions of this device, refer to the MAX4836/MAX4837.
Applications
SDIO Ports and Devices Notebook Computers
USB Ports and Devices Cell Phones
PDAs and Palmtop Devices GPS Systems
Features
oGuaranteed Minimum 250mA Load Current
oAccurate Current Limit
oPreset Output Voltages: 1.8V/2.5V/2.8V/3.0V/3.3V
o2.5V to 5.5V Supply Voltage Range
oAdjustable Soft-Start
oLow Dropout Voltage
oThermal Shutdown
oReverse-Current Protection
oShutdown Output Discharge (MAX4835)
oLow 90µA Supply Current
oUltra-Low 0.1µA Shutdown Current
oFLAG and Latch Off (MAX4834) or RESET
(MAX4835)
oTiny SOT23 and TDFN (3mm x 3mm) Packages
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
19-3373; Rev 1; 8/11
Note: “xy” are placeholders for the output voltage levels of the
devices. Insert the values found in Table 1 at the end of this doc-
ument in the place of “xy”. The “_” is a placeholder for either the
RESET or the FLAG feature. Insert “B” in the place of “_” for
RESET and “C” for FLAG. “dd” is a placeholder for the reset
timeout period. Insert the values found in Table 2 in the place of
“dd.” For example, MAX4835EUT18BD2 has a 1.8V output volt-
age, RESET feature, and a 30ms reset timeout period. Note that
“dd” applies only to the devices with RESET option and does not
apply to the devices with FLAG option. For devices with the
FLAG option, leave dd blank. Standard versions require a mini-
mum order increment of 2.5k units. Nonstandard versions must
be ordered in 10k unit increments. Contact factory for availability.
*
Future product—contact factory for availability.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
/V denotes an automotive qualified part.
*
EP = Exposed pad.
PART TEMP RANGE PIN-PACKAGE
MAX4834EUTxy_+T* -40°C to +85°C 6 SOT23
MAX4834ETTxy_+T -40°C to +85°C 6 TDFN-EP*
MAX4835EUTxy_dd+T* -40°C to +85°C 6 SOT23
MAX4835ETTxy_dd+T -40°C to +85°C 6 TDFN-EP*
MAX4835ETT18BD2/V+T -40°C to +85°C 6 TDFN-EP*
6OUT
5SS
4RESET
(FLAG)
1
2
GND
3
SHDN
MAX4834/MAX4835
IN
+
TDFN
EXPOSED PADDLE
TOP VIEW
( ) MAX4834ETTxyC ONLY.
Pin Configurations
Pin Configurations continued at end of data sheet.
Tables 1 and 2 and Selector Guide appear at end of data
sheet.
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN = VOUT + 1V, SHDN = IN, COUT = 3.3µF, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (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.
IN, SHDN, FLAG, OUT to GND ................................-0.3V to +6V
RESET to GND .........................................-0.3V to (VOUT + 0.3V)
SS to GND ...................................................-0.3V to (VIN + 0.3V)
IN to OUT ...............................................................................±6V
OUT Short Circuit to GND ..........................................Continuous
All Pins ESD Handling (Human Body Model).........................2kV
Continuous Power Dissipation (TA= +70°C)
6-Pin SOT23 (derate 9.1mW/°C above +70°C)................727mW
6-Pin TDFN (derate 24.4mW/°C above +70°C) ..........1951.2mW
Operating Temperature Range ...........................-40°C to +85°C
Operating Junction Temperature Range...........-40°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow) .......................................+260°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Operating Voltage VIN 2.5 5.5 V
Input Undervoltage Lockout
Threshold VUVLO VIN rising 2.00 2.25 V
Input Undervoltage Lockout
Threshold Hysteresis 50 mV
SHDN = IN, IOUT = 0A 90 150
SHDN = IN, IOUT = 0A,
VUVLO < VIN < VOUT (nominal) 150
Quiescent Current IQ
SHDN = GND, IOUT = 0A 0.1 2
µA
TA = +25°C 103 140
Dropout Voltage (Note 2) IOUT = 250mA TA = -40°C to +85°C 165 mV
IOUT = 1mA to 250mA, TA = +25°C -1.3 +1.3
Output Voltage Accuracy IOUT = 1mA to 250mA, TA = -40°C to +85°C -2 +2 %VNOM
Output Current IOUT 250 mA
Output Current Limit VOUT = 0V 270 330 mA
Reverse Current at VIN VOUT = 5.5V, VIN = 0V to VOUT 0.1 2 µA
CSS = not connected 0.5 1 2.0
CSS = 0.01µF 4 10 15
Soft-Start Time (Note 3) tSS
CSS = 0.1µF 40 100 150
ms
TA = +25°C -0.04 +0.02 +0.065
Line Regulation (Note 4) VOUT + 0.5V < VIN <
5.5V, ILOAD = 100µA TA = -40°C to +85°C -0.05 +0.03 +0.08
%VNOM/
V
Load Regulation 100µA < ILOAD < 250mA, VIN = VOUT + 1V 1.3 %VNOM
Output Noise 10Hz to 100kHz, CSS = 0.01µF 70 µVRMS
SHUTDOWN INPUT (SHDN)
OUT Discharge Resistance in
Shutdown (MAX4835) SHDN = GND 900 Ω
SHDN Input-Voltage High VIH 1.4 V
SHDN Input-Voltage Low VIL 0.5 V
SHDN Input Hysteresis 30 mV
SHDN Input Leakage Current SHDN = IN or GND -100 +100 nA
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
_______________________________________________________________________________________ 3
Note 1: Parts are 100% tested at +25°C. Limits across the full temperature range are guaranteed by design and correlation over the
specified temperature range.
Note 2: The dropout voltage is measured from VIN to VOUT when VOUT is 2% below its nominal value. The nominal output voltage is
measured from VOUT to GND when VIN is 1V greater than VOUT. Defined only for VOUT ≥2.5V.
Note 3: Soft-start time is defined as the time required for the output to rise from 10% of its nominal value to 90% of its nominal value.
Note 4: For VOUT < 2V, VIN must be above 2.5V.
Note 5: This is the maximum time OUT can be out of tolerance before a reset is issued. It is implemented to ensure that momentary
output glitches do not trigger a reset condition.
Note 6: In startup mode, the blanking time counter is not started until the soft-start time has elapsed. The total time from startup to
FLAG issued is tSS + tBLANK.
ELECTRICAL CHARACTERISTICS (continued)
(VIN = VOUT + 1V, SHDN = IN, COUT = 3.3µF, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
RESET OUTPUT (MAX4835)
RESET Threshold VRESET 0.85 x
VOUT
0.875 x
VOUT
0.90 x
VOUT V
OUT Drop to RESET Delay
(Note 5) tOR 35 µs
D1 timing option 2.5 3.75 5.0
D2 timing option 20 30 40
D3 timing option 150 225 300
RESET Timeout Period tRESET
D4 timing option 1200 1800 2400
ms
VOUT ≥ 1.0V, ISINK = 50µA, RESET asserted 0.3
RESET Output-Voltage Low VOUT ≥ 1.5V, ISINK = 3.2mA, RESET
asserted 0.4 V
RESET Output-Voltage High VOUT ≥ 2.0V, ISOURCE ≤ 500µA,
RESET deasserted
0.8 x
VOUT V
FLAG OUTPUT (MAX4834)
Blanking Time (Note 6) tBLANK VOUT + 1V ≤ VIN ≤ 5.5V, OUT = GND 5 10 17 ms
Open-Drain FLAG Output-
Voltage Low ISINK = 3.2mA, FLAG asserted, VOUT ≥ 1.5V 0.4 V
Open-Drain FLAG Leakage
Current VFLAG = 5.5V 0.01 1 µA
THERMAL PROTECTION
Thermal-Shutdown Temperature Junction temperature rising +165 °C
Thermal-Shutdown Hysteresis 15 °C
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
4 _______________________________________________________________________________________
Typical Operating Characteristics
(VIN = VOUT + 1V, SHDN = IN, COUT = 3.3µF, TA= +25°C, unless otherwise noted.)
QUIESCENT CURRENT vs. INPUT VOLTAGE
(NO LOAD)
MAX4834 toc01
VIN (V)
IQ (µA)
54321
20
40
60
80
100
120
0
06
TA = +85°C
TA = -40°C
TA = +25°C
VOUT = 1.5V
QUIESCENT CURRENT vs. INPUT VOLTAGE
(250mA LOAD)
MAX4834 toc02
VIN (V)
IQ (µA)
543210 6
TA = +85°C
TA = +25°C
VOUT = 3.3V
100
200
300
400
500
0
TA = -40°C
MAXIMUM TRANSIENT DURATION
vs. RESET THRESHOLD OVERDRIVE
MAX4834 toc03
RESET THRESHOLD OVERDRIVE (mV)
PULSE DURATION (µs)
10
15
30
45
60
75
90
0
1100
RESET ASSERTS
ABOVE THIS LINE
VIN = 3.5V
VOUT = 2.5V
DROPOUT VOLTAGE vs. LOAD CURRENT
MAX4834 toc04
LOAD CURRENT (mA)
DROPOUT VOLTAGE (mV)
20015010050
20
40
60
80
100
0
0250
VOUT = 3.3V
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX4834 toc05
FREQUENCY (kHz)
PSRR (dB)
1010.1
-70
-60
-50
-40
-30
-20
-10
0
-80
0.01 100
VOUT = 2V
COUT = 3.3µF
ILOAD = 20mA
REGION OF STABLE COUT ESR
vs. LOAD CURRENT
MAX4834 toc06
LOAD CURRENT (mA)
COUT ESR (Ω)
20015010050
1
2
3
4
5
6
7
0
0250
VOUT = 1.8V
COUT = 3.3µF
STABLE REGION
OUTPUT NOISE vs. FREQUENCY
MAX4834 toc07
FREQUENCY (Hz)
OUTPUT NOISE (µVRMS)
10k1k100
10
20
30
40
50
0
10 100k
VIN = 3V
VOUT = 1.8V
CSS = 10nF
ILOAD = 0
SOFT-START RESPONSE
(CSS = UNCONNECTED)
MAX4834 toc08
VSS
1V/div
VOUT
2V/div
VIN
2V/div
2ms/div
tSS
VOUT = 3.3V
_______________________________________________________________________________________ 5
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
SOFT-START RESPONSE
(CSS = 0.01µF)
MAX4834 toc09
VSS
1V/div
VOUT
2V/div
VIN
2V/div
2ms/div
tSS
SOFT-START RESPONSE
(CSS = 0.1µF)
MAX4834 toc10
VIN
2V/div
VSS
1V/div
VOUT
2V/div
20ms/div
tSS
LOAD-TRANSIENT RESPONSE
MAX4834 toc11
VOUT
50mV/div
AC-COUPLED
100µs/div
VIN = 4.3V
VOUT = 3.3V
CIN = 0.1µF
COUT = 3.3µF
ILOAD: STEP FROM 10mA TO 100mA
BACK TO 10mA
LOAD-TRANSIENT RESPONSE
NEAR DROPOUT
MAX4834 toc12
VOUT
50mV/div
AC-COUPLED
100µs/div
VIN = 3.4V
VOUT = 3.3V
CIN = 0.1µF
COUT = 3.3µF
ILOAD: STEP FROM 10mA TO 100mA
BACK TO 10mA
LINE-TRANSIENT RESPONSE
MAX4834 toc13
VOUT
50mV/div
AC-COUPLED
100µs/div
CIN = 0.1µF
COUT = 3.3µF
VOUT = 3.3V
ILOAD = 10mA
5V
VIN
500mV/div
4.5V
RESET RESPONSE TO VIN
MAX4834 toc14
VRESET
2V/div
VOUT
2V/div
VIN
2V/div
40ms/div
tRESET
CSS = UNCONNECTED
RESET RESPONSE TO VOUT
MAX4834 toc15
VRESET
1V/div
VOUT
1V/div
40ms/div
tRESET
VIN = 3.5V, CSS = UNCONNECTED
RESET RESPONSE TO SHUTDOWN
MAX4834 toc16
VRESET
2V/div
VOUT
2V/div
VSHDN
2V/div
40ms/div
tRESET
VIN = 3.5V, CSS = UNCONNECTED
Typical Operating Characteristics (continued)
(VIN = VOUT + 1V, SHDN = IN, COUT = 3.3µF, TA= +25°C, unless otherwise noted.)
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
6 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VIN = VOUT + 1V, SHDN = IN, COUT = 3.3µF, TA= +25°C, unless otherwise noted.)
FLAG RESPONSE WHEN OUT IS
SHORTED TO GND < BLANKING TIME
MAX4834 toc17
VOUT
1V/div
1ms/div
IOUT
200mA/div
VFLAG
2V/div
FLAG RESPONSE WHEN OUT IS
SHORTED TO GND > BLANKING TIME
(IN IS TOGGLED)
MAX4834 toc18
VOUT
1V/div
10ms/div
VIN
2V/div
VFLAG
2V/div
FLAG CONNECTED TO LOGIC SUPPLY
tBLANK
STARTUP IN AN OVERLOAD CONDITION
(CSS NOT CONNECTED)
MAX4834 toc20
VSS
1V/div
VFLAG
2V/div
VOUT
2V/div
2ms/div
tBLANK
VIN
2V/div
tSS
VOUT = 2.5V
ILOAD = ILIMIT MAXIMUM
FLAG CONNECTED TO LOGIC SUPPLY
STARTUP IN AN OVERLOAD CONDITION
(CSS = 0.01µF)
MAX4834 toc21
VSS
1V/div
VFLAG
2V/div
VOUT
2V/div
4ms/div
tBLANK
VIN
2V/div
tSS
VOUT = 2.5V
ILOAD = ILIMIT MAXIMUM
FLAG CONNECTED TO LOGIC SUPPLY
NORMALIZED OUTPUT VOLTAGE
vs. TEMPERATURE
MAX4834 toc22
TEMPERATURE (°C)
NORMALIZED OUTPUT VOLTAGE
603510-15
0.996
0.998
1.000
1.002
1.004
0.994
-40 85
NORMALIZED TO +25°C
ILOAD = 250mA
ILOAD = 100mA
ILOAD = 10mA
FLAG RESPONSE WHEN OUT IS
SHORTED TO GND > BLANKING TIME
(SHDN IS TOGGLED)
MAX4834 toc19
VOUT
1V/div
10ms/div
VSHDN
2V/div
VFLAG
2V/div
FLAG CONNECTED TO LOGIC SUPPLY
tBLANK
Detailed Description
The MAX4834/MAX4835 are ultra-low quiescent current,
low-dropout linear regulators with an integrated current
limiter. These devices guarantee up to 250mA drive
capabilities and regulate the preset output voltage.
The MAX4834 has a flag output that asserts low when
the load current exceeds the current limit for more than
the blanking time (tBLANK). The MAX4835 has a reset
output that asserts low when the regulator output volt-
age is below the reset threshold voltage (VRESET).
VRESET is 87.5% of the nominal output voltage. Figure 1
shows the simplified functional diagram and Figure 2
shows the typical application circuits.
FLAG
Output (MAX4834)
The open-drain FLAG output goes low and the LDO’s
pass transistor is latched off when the current in the
pass transistor is at its output current limit for more than
the blanking time (tBLANK). Cycling IN or SHDN (high to
low to high) brings the device out of its latched-off state
and back into normal operation.
RESET
Output (MAX4835)
The RESET output asserts when one of the following
conditions occurs:
• The input voltage (VIN) is below the input undervolt-
age lockout threshold (VUVLO).
• The output voltage (VOUT) is below the reset thresh-
old (VRESET).
•SHDN is pulled low.
• The device is in thermal shutdown.
• When VOUT > VIN.
RESET remains low for the reset timeout period (tRESET)
after reset conditions are terminated. There are four
RESET timeout periods available as shown in the
Electrical Characteristics
table. RESET is available in a
push-pull configuration as shown in the
Selector Guide
.
Shutdown
Pull SHDN low to shut down the LDO and reduce the
quiescent current consumption of the device from 90µA
to 0.1µA. In shutdown mode, the pass transistor, con-
trol circuit, and reference circuit are turned off. Connect
SHDN to a supply voltage greater than VIH to turn on
the LDO.
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
_______________________________________________________________________________________ 7
Pin Description
PIN
SOT23 TDFN NAME FUNCTION
11 IN
Regulator Power Input. Bypass IN to GND with a 0.1µF ceramic capacitor. Install the bypass
capacitor as close to the device as possible.
2 2 GND Ground
33SHDN Active-Low Shutdown Input. Drive SHDN low to shutdown the regulator. Drive SHDN high or
connect to IN for normal operation.
FLAG
(MAX4834)
Overcurrent Flag. Open-drain FLAG goes low when the device senses sustained current
exceeding the current-limit threshold for a duration longer than the blanking time. FLAG is high
when SHDN is low or the device is in thermal shutdown.
44
RESET
(MAX4835)
Active-Low Reset Output. Push-pull RESET goes low when the voltage at OUT is below the reset
threshold or when the voltage at OUT is greater than IN. RESET is low when SHDN is low or the
device is in thermal shutdown. After the reset condition terminates, RESET remains low for the
duration of the reset timeout period.
55 SS
Soft-Start Control. Connect a capacitor, CSS, from SS to GND to program the output rise time at
startup. No capacitor from SS to GND gives 1ms output rise time at startup. See the soft-start
response time plots in the Typical Operating Characteristics.
6 6 OUT Regulator Output. Bypass OUT to GND with a 3.3µF or larger ceramic capacitor. The capacitor’s
ESR should be less than 0.2Ω for stable operation.
—— EP
Exposed Pad (TDFN only). EP is internally connected to GND. Externally connect EP to GND to
provide a low thermal resistance path from the IC junction to the PC board.
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
8 _______________________________________________________________________________________
REVERSE-
CURRENT
PROTECTION
PASS
TRANSISTOR
RESET TIMEOUT
(BLANKING PERIOD)
OVERLOAD
PROTECTION
VSS
vFB
VREF
VFB
VREF
ERROR
AMPLIFIER
1.23V
90% x VREF
VREF
VSS = VREF
WHEN SOFT-START
IS COMPLETE
SWITCH OPEN
DURING SOFT-START
VSS
1.23µA
1nF
SWITCH
CLOSED IN
SHUTDOWN
MAX4835 ONLY
THERMAL
PROTECTION MAX4834/MAX4835
IN
SHDN
RESET
(FLAG)
GND
SS
OUT
900Ω
( ) MAX4834E_ _xyC ONLY.
Figure 1. Functional Diagram
MAX4834
LOAD
COUT
3.3µF
CSS
ON
OFF
OUT
SS
SHDN
FLAG
IN
GND
MAX4835
LOAD
COUT
3.3µF
CIN
0.1µF
2.5V TO 5.5V
CSS
TO µC
ON
OFF
OUT
SS
SHDN
RESET
IN
GND
CIN
0.1µF
2.5V TO 5.5V
TO µC
VLOGIC
Figure 2. Typical Application Circuits
Shutdown Discharge (MAX4835)
OUT discharges through a 900Ωinternal resistor during
shutdown mode.
Reverse OUT to IN Current
When the output voltage is greater than the input volt-
age, the internal pass transistor turns off. To avoid
reverse-charging the input source, the current at IN is
guaranteed to be below 3µA when VOUT ≥VIN.
Current Limit
The MAX4834/MAX4835 include an accurate internal
current-limiting circuit. OUT can be shorted to ground
indefinitely without damaging the part.
The MAX4834 latches off if the load current exceeds the
current limit for more than the blanking time (see the
FLAG Output
section). During soft-start, the device does
not latch off to an overload condition. During an overload
condition, the MAX4835 holds the current at current limit
until the thermal limit is reached. Once the junction tem-
perature reaches +165°C, thermal shutdown occurs.
Thermal Shutdown
When the junction temperature (TJ) exceeds +165°C,
the LDO’s pass transistor turns off allowing the junction
to cool. The LDO’s pass transistor turns on again after
the IC’s junction temperature cools by 15°C, resulting in
a pulsed output during continuous thermal overload
conditions.
Soft-Start
During power-up, the soft-start ensures that the output
ramps up slowly reducing inrush current peaks. See
the soft-start response time plots in the
Typical
Operating Characteristics
. The soft-start time (tSS) is
given by the following equation:
tSS = CSS (ms)
where CSS is in nF.
A soft-start capacitor (CSS) of 10nF gives a 10ms tSS. A
1ms minimum soft-start time is fixed internally to ensure
that the output rises slowly even without any external
capacitor at SS pin to ground. The device is in soft-start
mode when either the voltage at IN or SHDN is cycled
high to low to high.
Applications Information
Capacitor Selection and Regulator
Stability
For stable operation over the full temperature range and
with load currents up to 250mA, use a 3.3µF (min)
ceramic output capacitor with an ESR <0.2Ω. To reduce
noise and improve load transient response, stability, and
power-supply rejection, use larger output capacitor
values such as 10µF (note that some ceramic capacitors
exhibit large capacitance and ESR variation with temper-
ature). X7R capacitors provide good performance over
the -40°C to +85°C operating temperature range.
To improve power-supply rejection and transient
response, use a 0.1µF capacitor between IN and GND.
The MAX4834/MAX4835 remain stable with purely
resistive loads or current loads up to 250mA.
15kV Operational ESD Protection
A 3.3µF or higher value ceramic capacitor from OUT to
GND provides a 15kV (Human Body Model) protection
at OUT. The ESR value of the capacitor should be less
than 0.2Ω.
Reset Transient Immunity
The reset circuit is relatively immune to short duration,
falling VOUT transients. The
Typical Operating
Characteristics
show a graph of the Maximum Transient
Duration vs. Reset Threshold Overdrive for which reset is
not asserted. The graph was produced using falling VOUT
transients starting at VOUT and ending below the reset
threshold by the magnitude indicated (reset threshold
overdrive). The graph shows the maximum pulse width
that a falling VOUT transient can typically have without
triggering the reset pulse. As the amplitude of the tran-
sient increases (i.e., goes further below the reset thresh-
old), the maximum allowable pulse width decreases.
Typically, a VOUT transient that goes only 10mV below the
reset threshold and lasts up to 54µs does not trigger a
reset pulse.
Layout
When using the TDFN package, connect its exposed
paddle to GND to provide a low thermal resistance
path for heat transfer from the IC junction to the printed
circuit board.
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
_______________________________________________________________________________________ 9
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
10 ______________________________________________________________________________________
Selector Guide
PART PIN-
PACKAGE
OUTPUT
CURRENT (mA)
RESET OUTPUT
CONFIGURATION RESET (FLAG)SHUTDOWN
DISCHARGE LATCH OFF
MAX4834EUTxyC+T 6 SOT23 250 Open-Drain FLAG No Yes
MAX4834ETTxyC+T 6 TDFN 250 Open-Drain FLAG No Yes
MAX4835EUTxyBdd+T 6 SOT23 250 Push-Pull RESET Yes No
MAX4835ETTxyBdd+T 6 TDFN 250 Push-Pull RESET Yes No
MAX4835ETT18BD2/V+T 6 TDFN 250 Push-Pull RESET Yes No
Suffix ‘xy’ in the part number stands for nominal output voltage. 1.8V, 2.5V, 2.8V, 3.0V, 3.3V are the standard options. For other voltages
between 1.5V to 3.3V, contact factory.
Table 1. Standard Output Voltage Suffix
Guide
xy OUTPUT VOLTAGE (V)
18 1.8
25 2.5
28 2.8
30 3.0
33 3.3
Nonstandard output voltages from 1.5V to 3.3V are available in
100mV increments. Contact factory for availability.
Table 2. RREESSEETTTimeout Period Suffix
Guide
dd RESET TIMEOUT (ms)
D1 3.75
D2 30
D3 225
D4 1800
TOP VIEW
GND
SHDN
1 6 OUT
5SS
IN
MAX4834/
MAX4835
SOT23
2
34
RESET
(FLAG)
( ) MAX4834EUTxyC ONLY.
+
Pin Configurations (continued)
Chip Information
PROCESS: BiCMOS
TDFN Exposed Pad: Connected to GND
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE OUTLINE NO. LAND
PATTERN NO.
6 SOT23 U6F+6 21-0058 90-0175
6 TDFN T633+2 21-0137 90-0058
MAX4834/MAX4835
250mA LDO Linear Regulators with
Current-Limiting Switch
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________
11
© 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
07/04Initi al rel ease —
18/11
Added MAX4835ETT18BD2/V+T and lead-free versions of all parts to the
Ordering Information and Selector Guide 1, 10
