MAX38902D-27 [MAXIM]

12μVRMS Low Noise 500mA LDO Linear Regulator;
MAX38902D-27
型号: MAX38902D-27
厂家: MAXIM INTEGRATED PRODUCTS    MAXIM INTEGRATED PRODUCTS
描述:

12μVRMS Low Noise 500mA LDO Linear Regulator

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EVALUATION KIT AVAILABLE  
Click here for production status of specific part numbers.  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
LDO Linear Regulator  
RMS  
General Description  
The MAX38902A/B/C/D are low-noise, linear regulators  
Benefits and Features  
1.7V to 5.5V Input Voltage Range  
that deliver up to 500mA of output current with only  
0.6V to 5.3V Output Voltage Range  
12µV  
of output noise from 10Hz to 100kHz. These  
RMS  
12µV  
Output Noise, 10Hz to 100kHz  
RMS  
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 independent of drop-out voltage.  
365µA Operating Supply Current  
70dB PSRR at 10kHz  
500mA Maximum Output Current  
The MAX38902Ahave nine, pin-selectable output voltages  
1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.1V, 3.3V, 4.0V, and 5V. The  
MAX38902B/C have a resistor adjustable output voltage  
in the range of 0.6V to 5.3V. The MAX38902B also  
includes an active-low POK output.  
±1% DC Accuracy Over Load, Line,  
and Temperature  
100mV (Max) Dropout at 500mA Load (3.6V )  
IN  
< 0.1µA Shutdown Supply Current  
Stable with 2µF (Min) Output Capacitance  
Programmable Soft-Start Rate  
The MAX38902D have factory-preset output voltages  
ranging from 0.7V to 5V. All versions include a programmable  
output soft-start rate, output overcurrent and thermal  
overload protection.  
Overcurrent and Overtemperature Protection  
Output-to-Input Reversed Current Protection  
POK Output  
The MAX38902A/B are offered in an 8-pin TDFN package,  
while the MAX38902C/D are offered in a 2 x 3, 0.4mm  
wafer-level package (WLP).  
Pin-to-Pin compatible with MAX8902 (TDFN)  
1.22mm x 0.82mm, 2 x 3 Bump, 0.4mm Pitch WLP,  
Applications  
Communication Circuitry  
or 2mm x 2mm 8-pin TDFN Package  
Audio Systems  
Ordering Information appears at end of data sheet.  
High-Resolution Data Acquisition Systems  
19-100191; Rev 4; 10/18  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Typical Operating Circuits  
IN  
OUT  
(1.5V/500mA)  
IN  
OUT  
BYP  
(1.7V TO 5.5V)  
C1  
4.7µF  
C2  
10nF  
C3  
4.7µF  
GND  
MAX38902A  
TDFN  
ENABLE  
EN  
OUTS  
VOUT  
SELECT:  
TO GND,  
IN OR  
SELB  
SELA  
EP  
FLOAT  
OUTPUT ADJUSTABLE  
0.6V TO 5.3V  
IN  
(1.7V TO 5.5V)  
IN  
OUT  
BYP  
C1  
4.7µF  
C2  
10nF  
C3  
4.7µF  
GND  
EN  
GS  
R1  
100k  
MAX38902B  
TDFN  
____  
POK  
ENABLE  
RESET  
R3  
R2  
FB  
EP  
OUTPUT ADJUSTABLE  
0.6V TO 5.3V  
IN  
IN  
OUT  
BYP  
FB  
(1.7V TO 5.5V)  
C1  
4.7µF  
MAX38902C  
WLP  
C2  
10nF  
C3  
4.7µF  
GND  
EN  
R3  
R2  
ENABLE  
OUTPUT PRE-PROGRAMMED  
(0.7V TO 5.0V)  
IN  
IN  
OUT  
BYP  
(1.7V TO 5.5V)  
C1  
4.7µF  
MAX38902D-XX  
WLP  
C2  
10nF  
C3  
4.7µF  
GND  
EN  
ENABLE  
OUTS  
Maxim Integrated  
2  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Absolute Maximum Ratings  
IN, EN, POK, SELA, SELB, GS, OUTS,  
TDFN (derate 9.8mW/°C above 70°C)............................784mW  
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  
FB, BYP to GND..................................................-0.3V to +6V  
OUT to GND...................................................-0.3V to IN + 0.3V  
Output Short-Circuit Duration....................................Continuous  
Continuous Power Dissipation (TA = +70°C)  
WLP (derate 10.5mW/°C above 70°C)........................840mW  
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  
Outline Number  
21-0168  
90-0065  
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  
WLP  
PACKAGE CODE  
N60G1+1  
Outline Number  
21-100183  
Land Pattern Number  
Refer to Application Note 1891  
Thermal Resistance, Four-Layer Board:  
Junction to Ambient (θ  
)
95.1°C/W  
N/A  
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.  
Maxim Integrated  
3  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Electrical Characteristics  
(V = 3.6V, T = -40°C to +125°C, C  
= 10nF, C = 4.7µF, C  
= 4.7µF, Typical Operating Circuits. Typical values are at T = +25°C,  
IN  
J
BYP  
IN  
OUT J  
unless otherwise specified. (Note 1)  
PARAMETER  
Input Voltage Range  
Input Undervoltage Lockout  
Output Voltage Range  
Output Capacitance  
SYMBOL  
CONDITIONS  
MIN  
1.7  
1.5  
0.6  
2
TYP  
MAX  
5.5  
UNITS  
V
Guaranteed by Output Accuracy  
V
V
IN  
V
V
V
rising, 100mV hysteresis  
1.6  
1.7  
IN_UVLO  
IN  
IN  
V
C
> V  
+ 0.1V  
5.3  
V
OUT  
OUT  
For stability and proper operation  
4.7  
365  
0.01  
700  
µF  
OUT  
I
I
= 0mA  
600  
0.1  
Q
OUT  
µA  
nA  
Supply Current  
T = +25°C  
J
I
V
EN  
= 0V  
SHUTDOWN  
T = +125°C  
J
I
V
from 0.1mA to 500mA, V from  
IN  
OUT  
Output Accuracy  
(MAX38902A/D Only)  
ACC  
ACC  
+ 0.3V to 5.5V, V > 1.7V,  
-1  
+1  
%
38902A/D  
38902B/C  
OUT  
IN  
VOUT from 0.7V to 5.0V  
I from 0.1mA to 500mA, V from  
OUT  
Output Accuracy  
(MAX38902B/C Only)  
IN  
0.594  
0.6  
0.07  
50  
0.606  
V
%
V
+ 0.3V to 5.5V, V > 1.7V  
OUT IN  
I
V
from 0.1mA to 500mA,  
OUT  
Load Regulation  
Load Transient  
Line Regulation  
Line Transient  
= V  
+ 300mV , V  
= 2.5V  
IN  
OUT  
OUT  
I
t
= 50mA to 500mA to 50mA,  
OUT  
mV  
%
= t  
= 1µs  
RISE  
FALL  
V
V
from V  
+ 0.3V to 5.5V,  
IN  
IN  
OUT  
0.06  
3
> 1.7V, I  
= 200mA  
OUT  
V
t
= 4V to 5V to 4V, I  
= 500mA,  
IN  
OUT  
mV  
= t  
= 5µs  
RISE  
FALL  
V
= 3.6V TDFN  
= 3.6V WLP  
= 2.5V TDFN  
= 2.5V WLP  
= 1.7V TDFN  
= 1.7V WLP  
50  
30  
100  
100  
200  
200  
300  
300  
800  
IN  
V
IN  
V
58  
IN  
Dropout Voltage (Note 2)  
I
= 500mA  
mV  
mA  
OUT  
V
39  
IN  
V
84  
IN  
V
63  
IN  
Current Limit  
Output Noise  
V
= 0V, V - V  
= 500mV  
600  
700  
OUTS/FB  
IN  
OUT  
I
= 100mA,  
OUT  
C
= 47nF  
12  
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
Regulator remains stable  
0.001  
0.1  
1.2  
+1  
µF  
µA  
BYP  
From BYP to GND during startup  
50  
0.8  
EN rising  
EN falling  
V
from 1.7V  
IN  
EN Input Threshold  
V
to 5.5V  
0.4  
-1  
0.7  
T = +25°C  
J
+0.001  
0.01  
V
from 1.7V  
EN  
EN Input Leakage Current  
µA  
to 5.5V  
T = +125°C  
J
Maxim Integrated  
4  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Electrical Characteristics (continued)  
(V = 3.6V, T = -40°C to +125°C, C  
= 10nF, C = 4.7µF, C  
= 4.7µF, Typical Operating Circuits. Typical values are at T = +25°C,  
IN  
J
BYP  
IN  
OUT J  
unless otherwise specified. (Note 1)  
PARAMETER  
POK Threshold  
SYMBOL  
CONDITIONS  
MIN  
TYP  
91  
MAX  
UNITS  
V
rising  
falling  
88  
94  
V
when  
OUT  
OUT  
%
POK switches  
(MAX38902B Only)  
V
88  
OUT  
POK Voltage, Low  
(MAX38902B Only)  
I
= 1mA  
10  
100  
mV  
µA  
POK  
T = +25°C  
-0.1  
1
+0.001  
0.01  
+0.1  
J
POK Leakage Current  
(MAX38902B Only)  
V
= 5.5V  
POK  
T = +125°C  
J
When shorted to GND or IN.  
When Hi-Z  
500  
10  
Ω
SELA/B Input Resistance  
(MAX38902A Only)  
MΩ  
SELA/B Input Capacitance  
(MAX38902A Only)  
When Hi-Z  
pF  
Input Reverse-Current  
Threshold  
V
= 3.6V, when V falls to 0V  
200  
mA  
OUT  
IN  
T rising  
165  
150  
Thermal Shutdown  
Threshold  
T when output  
J
turns on/off  
J
°C  
T falling  
J
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 95% of its nominal value.  
IN  
OUT  
OUT  
Maxim Integrated  
5  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Typical Operating Characteristics  
(MAX38902A, V = 3.6V, V  
= 2.5V, T = 25°C, C = 4.7µF , C  
= 4.7µF, unless otherwise noted.)  
IN  
OUT  
A
IN  
OUT  
QUIESCENT CURRENT  
EN = HIGH, NO LOAD  
LINE REGULATION  
LOAD REGULATION  
toc02  
toc01  
toc03  
2.501  
2.500  
2.499  
2.498  
2.497  
2.496  
2.495  
2.494  
2.493  
2.492  
2.491  
450  
400  
350  
300  
250  
200  
150  
2.506  
2.8V INPUT  
200mALOAD  
2.504  
2.502  
2.500  
2.498  
2.496  
2.494  
2.492  
2.490  
1.5  
2.5  
3.5  
4.5  
5.5  
0
100  
200  
300  
400  
500  
1.5  
2.5  
3.5  
4.5  
5.5  
INPUT VOLTAGE (V)  
LOAD CURRENT (mA)  
INPUT VOLTAGE (V)  
LOAD TRANSIENT RESPONSE  
50mA TO 500mA TO 50mA  
LINE TRANSIENT RESPONSE  
STARTUP WAVEFORM  
toc05  
toc06  
toc04  
VIN  
2V/div  
50mV/div  
(AC-COUPLED)  
1V/div  
VOUT  
VEN  
500mV/div  
2.5V OUTPUT  
5Ω LOAD  
VOUT  
100mA/div  
IOUT  
2mV/div  
(AC COUPLED)  
VOUT  
5LOAD  
CBYP = 0.01µF  
IOUT  
200mA/div  
100ms/div  
100μs/div  
10 s/div  
OUTPUT NOISE SPECTRAL DENSITY  
vs. FREQUENCY  
PSRR vs. FREQUENCY  
DROPOUT VOLTAGE vs. LOAD CURRENT  
toc08  
toc07  
toc09  
0
-10  
-20  
-30  
-40  
-50  
-60  
-70  
50  
45  
40  
35  
30  
25  
20  
15  
10  
5
10E-6  
1E-6  
INPUT = 3.6V,  
V
C
= 3.7V, V  
= 3.3V, I  
= 400mA  
= 3 x 4.7µF  
IN  
OUT  
OUT  
V
C
= 3.7V, V  
= 3.3V, I  
= 400mA  
= 3 x 4.7µF  
IN  
OUT  
OUT  
OUTPUT TARGET = 4.0V.  
THE SLOPE OF THE LINE  
INDICATES ON-RESISTANCE  
IN DROPOUT  
=100nF , C = C  
BYP  
IN  
OUT  
=100nF , C = C  
BYP  
IN  
OUT  
TDFN  
WLP  
100E-9  
10E-9  
0
100  
1k  
10k  
100k  
1M  
10M  
0
100  
200  
300  
400  
500  
10  
100  
1k  
10k  
100k  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
IOUT (mA)  
Maxim Integrated  
6  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Pin Configurations  
MAX38902A  
MAX38902B  
IN  
GND  
EN  
1
2
3
4
8
7
6
5
OUT  
IN  
GND  
EN  
1
2
3
4
8
7
6
5
OUT  
BYP  
FB  
BYP  
Exposed  
Pad  
Exposed  
Pad  
OUTS  
SELB  
____  
POK  
SELA  
GS  
MAX38902C  
MAX38902D  
TOP VIEW (BUMP-SIDE DOWN)  
TOP VIEW (BUMP-SIDE DOWN)  
1
2
3
1
2
3
A
B
IN  
GND  
EN  
A
B
IN  
GND  
EN  
OUT  
BYP  
FB  
OUT  
BYP  
OUTS  
Maxim Integrated  
7  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Pin Description  
PIN  
NAME  
FUNCTION  
MAX38902A MAX38902B MAX38902C MAX38902D  
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
2
1
2
A1  
A2  
A1  
A2  
IN  
Regulator Ground. Bring IN and OUT bypass capacitor  
GND connections to this pin for best performance.  
GND  
Enable Input. Connect this pin to a logic signal to  
enable (V  
high) or disable (V  
low) the regulator  
EN  
EN  
3
3
A3  
A3  
EN  
output. Connect to IN to keep the output enabled when-  
ever 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 low  
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.  
B3  
OUTS  
Feedback Divider Input. Connect a resistor divider  
string from OUT to GND with the midpoint tied to this  
pin to set the output voltage. In the Typical Operating  
7
6
7
B3  
B2  
B1  
B2  
B1  
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.  
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.  
8
8
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  
Maxim Integrated  
8  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Simplified Functional Diagram  
IN  
CURRENT  
LIMIT  
THERMAL  
PROTECTION  
REVERSE  
CURRENT  
PROTECTION  
EN  
CONTROL  
OUT  
BYP  
EA  
BYP  
REF  
0.6V  
MAX38902B ONLY  
POK  
MAX38902A  
MAX38902B  
MAX38902C  
MAX38902D  
0.54V  
MAX38902B/C ONLY  
FB  
OUTS  
MAX38902A ONLY  
MAX38902A/D only  
SELA  
SELB  
VOLTAGE  
SELECT  
GND  
Maxim Integrated  
9  
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MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Protection Features  
Detailed Description  
The MAX38902A/B/C/D 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 reestablish regulation. While the fault  
persists, the output current cycles on and off, as the junc-  
tion temperature slews between 150°C and 165°C.  
The MAX38902A/B/C/D low noise linear regulators deliver  
up to 500mAof output current with only 12µV  
of output  
RMS  
noise in a 10Hz to100kHz bandwidth. These regulators  
maintain their output voltage over a wide input range, requir-  
ing only 100mV of input-to-output headroom at full load.  
The MAX38902 maintains a low 365µA typical supply  
current, independent of the load current and drop-out  
voltage. The regulator control circuitry includes a pro-  
grammable soft-start circuit, short-circuit, reverse input  
current, and thermal overload protection. Other features  
include an enable input and power-okay (POK) output  
(MAX38902B only). See Functional Diagram.  
The MAX38902A/B/C/D 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 MAX38902A/B/C/D include a reverse volt-  
age detector that trips when IN drops 10mV below OUT,  
shutting off the regulator and opening the PMOS body  
diode connection, preventing any reverse current.  
Enable (EN)  
The MAX38902A/MAX38902B/MAX38902C/MAX38902D  
include an enable input (EN). Pull EN low to shut down  
the output, or drive EN high to enable the output. If a sep-  
arate shutdown signal is not available, connect EN to IN.  
Bypass (BYP)  
Output Voltage Configuration (MAX38902A)  
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 around 32Hz.  
The MAX38902A 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.  
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 start-up 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:  
Table 1. MAX38902A Output Configuration  
V
(V)  
SELA STATE  
SELB STATE  
OUT  
1.2  
1.5  
1.8  
2.5  
3.0  
3.1  
3.3  
4.0  
5.0  
Unconnected  
IN  
Startup Slew Rate = (5V ms)×(0.01µF/CBYP)  
IN  
Unconnected  
GND  
Unconnected  
where C  
is in µF.  
BYP  
Unconnected  
Unconnected  
GND  
Notethatthisslewrateappliesonlyatstartup.Thatrecovery  
from a short-circuit will occur at a slew rate approximately  
500 times slower.  
GND  
GND  
GND  
IN  
IN  
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.  
Unconnected  
GND  
IN  
IN  
Maxim Integrated  
10  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Output Voltage Configuration (MAX38902B/C)  
Output Voltage Configuration (MAX38902D)  
The MAX38902B and MAX38902C use external feed-  
back resistors to set the output regulation voltage as  
shown in Typical Operating Circuits. 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:  
The MAX38902D output voltage comes pre-programmed  
to values listed below. Additionally, any voltage between  
0.7V and 5.3V in 50mV steps can be factory trimmed, and  
special ordered.  
Power-OK (MAX38902B)  
The MAX38902B includes an additional open-drain out-  
put, POK, that goes low to indicate the output voltage is  
in regulation. Connect a pullup resistor from this pin to an  
external supply. During startup, POK stays high until the  
output voltage rises to 91%(typ) of its regulation level. If  
an overload occurs at the output, or the output is shut-  
down, POK goes high.  
V
OUT  
R3 = R2×  
- 1  
V
FB  
where V is the feedback regulation voltage of 0.6V. To  
FB  
set the output voltage to 2.5V, for example, R3 should be:  
Input Capacitor  
2.5V  
0.6V  
R3 = 300kΩ ×  
- 1 = 950kΩ  
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.  
Table 2. MAX38902D Output Voltage  
Output Capacitor  
PART NUMBER  
MAX38902D-07  
V
OUT  
A minimum of 2µF capacitance is required at OUT to  
ensure stability. Select a ceramic capacitor that main-  
tains 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.  
0.7V  
0.8V  
1.0V  
1.2V  
1.5V  
1.8V  
2.0V  
2.5V  
2.7V  
3.0V  
3.3V  
4.6V  
5.0V  
MAX38902D-08  
MAX38902D-10  
MAX38902D-12  
MAX38902D-15  
MAX38902D-18  
MAX38902D-20  
MAX38902D-25  
MAX38902D-27  
MAX38902D-30  
MAX38902D-33  
MAX38902D-46  
MAX38902D-50  
Thermal Considerations  
The MAX38902A/B is 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 there-  
fore 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.  
Ordering Information  
PART NUMBER  
MAX38902AATA+  
TEMPERATURERANGE  
-40°C to +125°C  
-40°C to +125°C  
-40°C to +125°C  
-40°C to +125°C  
-40°C to +125°C  
-40°C to +125°C  
PIN-PACKAGE  
OUTPUT VOLTAGE SETTING  
8 TDFN  
8 TDFN  
6 WLP  
6 WLP  
6 WLP  
6 WLP  
Pin-Selectable Output Voltage  
MAX38902BATA+  
External Resistor Feedback with POK output  
External Resistor Feedback  
MAX38902CANT+  
MAX38902DANT_ _+  
MAX38902DANT27+  
MAX38902DANT46+  
Factory-trimmed option from 0.7V to 5.0V  
Factory-trimmed option from 0.7V to 5.0V  
Factory-trimmed option from 0.7V to 5.0V  
+Denotes a lead(Pb)-free/RoHS-compliant package.  
Maxim Integrated  
11  
www.maximintegrated.com  
MAX38902A/MAX38902B/  
MAX38902C/MAX38902D  
12μV  
Low Noise 500mA  
RMS  
LDO Linear Regulator  
Revision History  
REVISION REVISION  
PAGES  
CHANGED  
DESCRIPTION  
NUMBER  
DATE  
11/17  
1/18  
0
1
2
Initial release  
11  
11  
Updated future product status of MAX38902BATA+  
Updated Ordering Information table  
4/18  
Updated Electrical Characteristics, Benefits and Features, and Ordering Information  
sections  
3
4
8/18  
1, 4, 11  
1, 4, 11  
Updated Electrical Characteristics, Benefits and Features, Typical Operating  
Characteristics, and Ordering Information sections  
10/18  
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.  
2018 Maxim Integrated Products, Inc.  
12  

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