High-Efficiency, 2A, Current-Mode

Synchronous, Step-Down Switching Regulator

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Pin Description

Pin Configuration

BUMP

NAME

FUNCTION

A1

GND

Analog Ground/Low-Side Switch Source Terminal. Connect to the PCB copper plane at one point near

the input bypass capacitor return terminal.

A2

LX

Inductor Connection. Connect LX to the switched side of the inductor. LX is high impedance when the

IC is in shutdown mode.

A3

IN

Input Power Supply. Input supply range is from 2.7V to 5.5V. Bypass with a minimum 10FF ceramic

capacitor to GND. See Figures 5 and 6.

B1

COMP

Voltage Error-Amplifier Output. Connect the necessary compensation network from COMP to GND. See

the Closing the Loop: Designing the Compensation Circuitry section.

B2

SKIP

Skip-Mode Input. Connect to EN to select skip mode or leave unconnected for normal operation.

B3

EN

Enable Input. EN is a digital input that turns the regulator on and off. Drive EN high to turn on the regula-

tor. Connect to IN for always-on operation.

C1

FB

Feedback Input. Connect FB to the center tap of an external resistor-divider from the output to GND to

C2

SS/REFIN

Soft-Start/External Voltage Reference Input. Connect a capacitor from SS/REFIN to GND to set the startup

time. See the Setting the Soft-Start Time section for details on setting the soft-start time. Apply a voltage

C3

PGOOD

Open-Drain Power-Good Output. PGOOD goes high when FB is above 555mV and pulls low if FB is

below 527mV.

WLP

TOP VIEW

(BUMPS ON BOTTOM)

SS/REFIN

FB

PGOOD

SKIP

COMP

EN

LX

GND

IN

MAX15053

A1

B1

C1

C2

C3

B2

B3

A3

A2