MAX25300AATA [MAXIM]
12μVRMS Low Noise 500mA LDO Linear Regulator;
| 型号： | MAX25300AATA |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | 12μVRMS Low Noise 500mA LDO Linear Regulator |
| 文件： | 总16页 (文件大小：468K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear
Regulator
RMS
General Description
Benefits and Features
The MAX25300A/B are low-noise linear regulators that de-
● 1.7V to 5.5V Input Voltage Range
● 0.6V to 5.3V Output Voltage Range
liver up to 500mA of output current with only 12µV
RMS
of output noise from 10Hz to 100kHz. These regulators
maintain ±1% output accuracy over a wide input voltage
range, requiring only 100mV of input-to-output headroom
at full load. The 365µA no-load supply current is indepen-
dent of dropout voltage.
● 12µV
Output Noise, 10Hz to 100kHz
RMS
● 365µA Operating Supply Current
● 70dB PSRR at 10kHz
● 500mA Maximum Output Current
● ±1% DC Accuracy Over Load, Line, and Temperature
● 100mV (Max) Dropout at 500mA Load (3.6V )
IN
The MAX25300A has nine pin-selectable output voltages:
1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.1V, 3.3V, 4.0V, and 5V.
The MAX25300B has a resistor adjustable output voltage
in the range of 0.6V to 5.3V. The MAX25300B also in-
cludes an active-high POK output.
● < 0.1µA Shutdown Supply Current
● Stable with 2µF(Min) Output Capacitance
● Programmable Soft-Start Rate
● Overcurrent and Overtemperature Protection
● Output-to-Input Reversed Current Protection
● POK Output
The MAX25300A/B are offered in an 8-pin TDFN package.
● 2mm x 2mm 8-pin TDFN Package
● AEC-Q100
Applications
● Automotive Electronics
● -40°C to 125°C Operating Temperature
● Audio Systems
● High-Resolution Data Acquisition Systems
Ordering Information appears at end of datasheet.
19-100781; Rev 0; 6/20
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Typical Operating Circuits
IN
OUT
IN
OUT
(1.7V to 5.5V)
(1.5V/500mA)
CIN
4.7µF
CBYP
10nF
COUT
4.7µF
GND
BYP
MAX25300A
TDFN
OUTS
ENABLE
EN
SELA
SELB
V
SELECT:
TO GND,
OUT
IN OR FLOAT
Hi-Z
EP
OUTPUT ADJUSTABLE
(0.6V TO 5.3V)
IN
OUT
IN
(1.7V to 5.5V)
CIN
4.7µF
COUT
4.7µF
CBYP
10nF
R1
100k
GND
EN
BYP
POK
FB
MAX25300B
TDFN
RESET
ENABLE
R3
R2
GS
EP
19-100781
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Maxim Integrated | 2
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
TABLE OF CONTENTS
General Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Benefits and Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Typical Operating Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
TDFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Pin Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
MAX25300A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
MAX25300B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Functional Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Simplified Functional Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Enable (EN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Bypass (BYP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Protection Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Output Voltage Configuration (MAX25300A) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Output Voltage Configuration (MAX25300B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Power-OK (MAX25300B) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Input Capacitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Output Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Thermal Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Typical Application Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
19-100781
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Maxim Integrated | 3
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
LIST OF TABLES
Table 1. MAX25300A Output Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
19-100781
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Maxim Integrated | 4
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Absolute Maximum Ratings
IN, EN, POK, SELA, SELB, GS, OUTS, FB, BYP to GND...-0.3V
Operating Temperature Range...........................-40°C to +125°C
Maximum Junction Temperature ......................................+150°C
Storage Temperature Range ..............................-65°C to +150°C
Lead Temperature (Soldering, 10 seconds) .....................+300°C
Soldering Temperature (reflow) ........................................+260°C
to +6V
OUT to GND.....................................................-0.3V to IN + 0.3V
Output Short-Circuit Duration ..................................... Continuous
Continuous Power Dissipation (T = +70°C) .
A
TDFN (derate 9.8mW/°C above 70°C) ......................... 784mW
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.
Package Information
TDFN
Package Code
T822+3C
21-0168
90-0065
Outline Number
Land Pattern Number
Thermal Resistance, Single-Layer Board:
Junction to Ambient (θ
)
130°C/W
8°C/W
JA
Junction to Case (θ
)
JC
Thermal Resistance, Four-Layer Board:
Junction to Ambient (θ
)
102°C/W
8°C/W
JA
Junction to Case (θ
)
JC
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.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 thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal
considerations, refer to www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
(V = 3.6V, T = -40°C to +125°C, C
= 10nF, C = 4.7µF, C
= 4.7µF, typical values are at T = +25°C, unless otherwise
OUT J
IN
J
BYP
IN
specified. (Note 1))
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Input Voltage Range
V
IN
Guaranteed by Output Accuracy
1.7
5.5
V
Input Undervoltage
Lockout
V
V
rising, 100mV hysteresis
1.5
1.6
1.7
5.3
V
IN_UVLO
IN
IN
Output Voltage Range
Output Capacitance
V
C
V
> V
+ 0.1V
OUT
0.6
2
V
OUT
For stability and proper operation
4.7
365
µF
OUT
I
I
= 0mA
600
0.1
Q
OUT
µA
Supply Current
T = +25°C
0.01
2400
J
I
V
EN
= 0V
SHUTDOWN
T = +125°C
J
nA
%
Output Accuracy
(MAX25300A Only)
I
from 0.1mA to 500mA, V from
+ 0.3V to 5.5V, V > 1.7V
OUT IN
ACC
ACC
-1
+1
25300A
25300B
V
OUT IN
Output Accuracy
(MAX25300B Only)
I
from 0.1mA to 500mA, V from
+ 0.3V to 5.5V, V > 1.7V
OUT IN
0.594
0.6
0.606
V
V
OUT IN
I
from 0.1mA to 500mA, V = V
IN OUT
OUT
Load Regulation
0.07
%/V
+ 300mV , V
= 2.5V
OUT
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Maxim Integrated | 5
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Electrical Characteristics (continued)
(V = 3.6V, T = -40°C to +125°C, C
= 10nF, C = 4.7µF, C
= 4.7µF, typical values are at T = +25°C, unless otherwise
OUT J
IN
J
BYP
IN
specified. (Note 1))
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
I
t
= 50mA to 500mA to 50mA, t
= 1µs
=
RISE
OUT
Load Transient
Line Regulation
Line Transient
50
mV
FALL
V
from V
+ 0.3V to 5.5V, V
>
IN
IN
OUT
0.06
3
%/V
mV
1.7V, I
= 200mA
OUT
V
= 4V to 5V to 4V, I
= 500mA,
OUT
IN
t
= t
= 5µs
FALL
RISE
V
V
V
V
= 3.6V
= 2.5V
= 1.7V
= 1.7V
26
36
100
200
300
800
IN
IN
IN
IN
Dropout Voltage (Note
2)
I
= 500mA
mV
mA
OUT
63
V
V
= 0V,
600
600
700
OUTS/FB
Current Limit
Output Noise
- V
=
IN
OUT
V
IN
= 3.6V
700
12
800
500mV
I
= 100mA,
OUT
C
= 47nF
µV
RMS
BYP
10Hz to 100kHz
f = 1kHz
70
70
60
40
f = 10kHz
f = 100kHz
f = 1MHz
Power Supply Rejection
Ratio
PSRR
I
= 100mA
dB
OUT
BYP Capacitor Range
BYP Soft-Start Current
C
BYP
Regulator remains stable
0.001
0.1
1.2
+1
µF
µA
From BYP to GND during startup
50
0.8
EN rising
EN falling
V
5.5V
from 1.7V to
IN
EN Input Threshold
V
0.4
-1
0.7
T = +25°C
J
+0.001
0.01
91
EN Input Leakage
Current
V
EN
from 1.7V to
µA
5.5V
T = +125°C
J
V
rising
falling
88
94
POK Threshold
(MAX25300B Only)
V
when POK
OUT
OUT
OUT
%
mV
µA
switches
V
88
POK Voltage, Low
(MAX25300B Only)
I
= 1mA
10
100
POK
T = +25°C
-0.1
1
+0.001
0.01
+0.1
POK Leakage Current
(MAX25300B Only)
J
V
POK
= 5.5V
T = +125°C
J
SELA/B Input
Resistance
(MAX25300A Only)
When shorted to GND or IN.
When Hi-Z
500
10
Ω
MΩ
SELA/B Input
Capacitance
When Hi-Z
pF
(MAX25300A Only)
Input Reverse Current
Threshold
V
= 3.6V, when V falls to 0V
200
mA
°C
OUT
IN
T rising
J
165
150
Thermal Shutdown
Threshold
T when output
J
turns on/off
T falling
J
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Maxim Integrated | 6
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Note 1: Limits over the specified operating temperature and supply voltage range are guaranteed by design and characterization, and
production tested at T = 25ºC only.
J
Note 2: Dropout voltage is defined as (V - V
), when V
is 5% lower than the value of V
when V = V
+ 0.5V.
OUT
IN
OUT
OUT
OUT
IN
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Maxim Integrated | 7
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Typical Operating Characteristics
(MAX25300B, V = 5.0V, V
= 3.3V, T = 25°C, C = 4.7µF , C
= 4.7µF, unless otherwise noted.)
OUT
IN
OUT
A
IN
4.2V INPUT
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Maxim Integrated | 8
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Pin Configurations
MAX25300A
Top View (Pad-Side Down)
OUT
1
2
3
4
8
7
6
5
IN
GND
EN
BYP
Exposed
Pad
OUTS
SELB
SELA
8-pin TDFN 3mm x 3mm
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Maxim Integrated | 9
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
MAX25300B
Top View (Pad-Side Down)
IN
OUT
1
2
3
4
8
7
6
5
GND
BYP
FB
Exposed
Pad
EN
GS
POK
8-pin TDFN 3mm x 3mm
Pin Description
PIN
NAME
FUNCTION
MAX25300A
MAX25300B
Regulator Supply Input. Connect to a voltage between 1.7V and 5.5V and bypass
with a 4.7µF capacitor from IN to GND.
1
1
IN
Regulator Ground. Bring IN and OUT bypass capacitor GND connections to this
pin for best performance.
2
3
2
3
GND
Enable Input. Connect this pin to a logic signal to enable (V
high) or disable
EN
EN
(V
low) the regulator output. Connect to IN to keep the output enabled
EN
whenever a valid supply voltage is present.
Output Select Input. Connect to GND, IN or leave unconnected to select one of
three states. The state of the SELA and SELB pins are read when the device is
enabled and used to select one of nine output voltages.
4
—
5
—
4
SELA
GS
Ground Sense. Connect GS to GND.
Output Select Input. Connect to GND, IN or leave unconnected to select one of
three states. The state of the SELA and SELB pins are read when the device is
enabled and used to select one of nine output voltages.
—
SELB
Power On Reset Output. Connect a pullup resistor from this pin to a supply to
create a reset signal that goes high after the regulator output has reached its
regulation voltage.
—
6
5
POK
Output Voltage Sense Input. Connect to the load at a point where accurate
regulation is required to eliminate resistive metal drops.
—
OUTS
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Maxim Integrated | 10
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Pin Description (continued)
PIN
NAME
FUNCTION
MAX25300A
MAX25300B
Feedback Divider Input. Connect a resistor divider string from OUT to GND with
the mid-point tied to this pin to set the output voltage. In the Typical Application
—
6
FB
BYP
OUT
EP
Circuits, V
= 0.6V x (1 + R3/R2).
OUT
Bypass Capacitor Input. Connect a 0.001µF to 0.1µF capacitor between OUT and
BYP to reduce output noise and set the regulator soft-start rate.
7
8
7
8
Regulator Output. Sources up to 500mA at the output regulation voltage. Bypass
with a 4.7µF (2µF minimum including voltage derating) low ESR (<0.03Ω)
capacitor to GND.
Exposed Pad (TDFN only). Connect the exposed pad to a ground plane with low
thermal resistance to ambient to provide best heat sinking.
EP
EP
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Maxim Integrated | 11
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Functional Diagrams
Simplified Functional Diagram
IN
CURRENT
LIMIT
THERMAL
PROTECTION
REVERSE
CURRENT
PROTECTION
EN
CONTROL
OUT
BYP
EA
BYP
REF
0.6V
MAX25300B ONLY
POK
MAX25300A
MAX25300B
0.54V
MAX25300B ONLY
FB
OUTS
MAX25300A ONLY
MAX25300A ONLY
SELA
SELB
VOLTAGE
SELECT
GND
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Maxim Integrated | 12
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Detailed Description
The MAX25300A/B low noise linear regulators deliver up to 500mA of output current with only 12µV
of output noise
RMS
in a 10Hz to100kHz bandwidth. These regulators maintain their output voltage over a wide input range, requiring only
100mV of input-to-output headroom at full load.
The MAX25300A/B maintain a low 365µA typical supply current, independent of the load current and dropout voltage.
The regulator control circuitry includes a programmable soft-start circuit, short-circuit, reverse input current, and thermal
overload protection. Other features include an enable input and power-okay (POK) output (MAX25300B only). See
Functional Diagrams.
Enable (EN)
The MAX25300A/MAX25300B include an enable input (EN). Pull EN low to shut down the output, or drive EN high to
enable the output. If a separate shutdown signal is not available, connect EN to IN.
Bypass (BYP)
The capacitor connected from BYP to OUT filters the noise of the reference, feedback resistors and regulator input stage,
and provides a high-speed feedback path for improved transient response. A 0.01µF capacitor rolls off input noise at
approximately 32Hz.
The slew rate of the output voltage during startup is also determined by the BYP capacitor. A 0.01µF capacitor sets the
slew rate to 5V/ms. This startup rate results in a 50mA slew current drawn from the input at startup to charge the 10µF
output capacitance.
The BYP capacitor value can be adjusted from 0.001µF to 0.1µF to change the startup slew rate according to the
following formula:
StartupSlewRate = 5V ms × 0.01 µ F C
(
/
)
(
/
)
BYP
where C
is in µF.
BYP
Note that this slew rate applies only at startup. Recovery from a short circuit will occur at a slew rate approximately 500
times slower.
Also note that, being a low-frequency filter node, BYP is sensitive to leakage. BYP leakage currents above 10nA cause
measurable inaccuracy at the output and should be avoided.
Protection Features
The MAX25300A/B are fully protected from an output short circuit by a current-limiting and thermal-overload circuit. If the
output is shorted to GND, the output current is limited to 700mA (typ). Under these conditions, the part quickly heats up.
When the junction temperature reaches 165°C, a thermal limit circuit shuts off the output device. When the junction cools
to 150°C, the output turns back on in an attempt to re-establish regulation. While the fault persists, the output current
cycles on and off, as the junction temperature slews between 150°C and 165°C.
The MAX25300A/B are also protected against reverse current when the output voltage is higher than the input. In the
event that extra output capacitance is used at the output, a power-down transient at the input would normally cause a
large reverse current through a conventional regulator. The MAX25300A/B include a reverse-voltage detector that trips
when IN drops 10mV below OUT, shutting off the regulator and opening the pMOS body diode connection, preventing
any reverse current. Once the reverse voltage is removed, the output will start up again.
Output Voltage Configuration (MAX25300A)
The MAX25300A output can be set to one of nine voltages by shorting or opening the SELA and SELB inputs, as shown
in Table 1. SELA and SELB should be connected to GND, IN, or left unconnected. Alternatively, they may be driven high,
low, or open with external logic. However, the states of SELA and SELB are sampled only at startup. The regulation
voltage can be set to a different level by cycling EN or IN momentarily to GND.
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Maxim Integrated | 13
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Table 1. MAX25300A Output Configuration
V
(V)
SELA STATE
Unconnected
IN
SELB STATE
IN
OUT
1.2
1.5
1.8
2.5
3.0
3.1
3.3
4.0
5.0
Unconnected
GND
Unconnected
Unconnected
GND
Unconnected
GND
GND
IN
GND
Unconnected
GND
IN
IN
IN
Output Voltage Configuration (MAX25300B)
The MAX25300B uses external feedback resistors to set the output regulation voltage, as shown in Functional Diagrams.
The output can be set from 0.6V to 5.3V. Set the lower feedback resistor R2 to 300kΩ or less to minimize FB input bias
current error. Then calculate the value of the upper feedback resistor R3 as follows:
V
OUT
R3 = R2 ×
− 1
V
(
)
FB
where V
is the feedback regulation voltage of 0.6V. To set the output voltage to 2.5V, for example, R3 should be:
FB
2.5V
0.6V
R3 = 300kΩ ×
− 1 = 950kΩ
)
(
Power-OK (MAX25300B)
The MAX25300B includes an additional open-drain output, POK, that goes high to indicate the output voltage is in
regulation. Connect a pullup resistor from this pin to an external supply. During startup, POK stays low until the output
voltage rises to 91%(typ) of its regulation level. If an overload occurs at the output, or the output is shutdown, POK goes
low.
Input Capacitor
A 4.7µF ceramic capacitor is recommended for the input. Select a capacitor that maintains its capacitance over
temperature and DC bias. Capacitors with X5R or X7R temperature characteristics generally perform well.
Output Capacitor
A minimum of 2µF capacitance is required at OUT to ensure stability. Select a ceramic capacitor that maintains its
capacitance (2µF minimum) over temperature and DC bias. Capacitors with X5R or X7R temperature characteristics
generally perform well. For example, the ceramic capacitor part number GRM155R60J475ME47 from Murata (4.7µF/
6.3V/X5R ) derates to around 2.9µF with 1.8V DC bias.
Thermal Considerations
The MAX25300A/B are packaged in an 8-pin 2mm x 2mm TDFN package with an exposed paddle. The exposed paddle
is the main path for heat to leave the IC, and therefore must be connected to a ground plane with thermal vias to allow
heat to dissipate from the device. Thermal properties of the IC package are given in the Package Information section.
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Maxim Integrated | 14
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Typical Application Circuits
Typical Application Circuit
IN
OUT
IN
OUT
(1.7V to 5.5V)
(1.5V/500mA)
CIN
4.7µF
CBYP
10nF
COUT
4.7µF
GND
BYP
MAX25300A
TDFN
OUTS
ENABLE
Hi-Z
EN
SELA
SELB
V
SELECT:
TO GND,
OUT
IN OR FLOAT
EP
OUTPUT ADJUSTABLE
(0.6V TO 5.3V)
IN
OUT
IN
(1.7V to 5.5V)
CIN
4.7µF
COUT
4.7µF
CBYP
10nF
R1
100k
GND
EN
BYP
POK
FB
MAX25300B
TDFN
RESET
ENABLE
R3
R2
GS
EP
Ordering Information
PART NUMBER
MAX25300AATA/V+
MAX25300BATA/V+
TEMPERATURE RANGE
PIN-PACKAGE
8 TDFN
OUTPUT VOLTAGE SENSING
-40°C to +125°C
Pin-Selectable Output Voltage
-40°C to +125°C
8 TDFN
External Resistor Feedback with POK output
/V Denotes an automotive qualified part.
+Denotes a lead(Pb)-free/RoHS-compliant package.
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Maxim Integrated | 15
MAX25300A/MAX25300B
12µV
Low Noise 500mA LDO Linear Regulator
RMS
Revision History
REVISION REVISION
PAGES
CHANGED
DESCRIPTION
NUMBER
DATE
0
6/20
Initial release
—
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent
licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max
limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2020 Maxim Integrated Products, Inc.
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