Data Sheet

ADP2138/ADP2139

Rev. C | Page 5 of 20

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

VIN

EN

SW

GND VOUT

1

2

3

4

5

6

MODE

TOP VIEW

(BALL SIDE DOWN)

Not to Scale

Figure 2. Pin Configuration (Top View)

Table 5. Pin Function Descriptions

Pin No.

Mnemonic

Description

1

VIN

Power Source Input. VIN is the source of the PFET high-side switch. Bypass VIN to GND with a 4.7 μF or greater

capacitor as close to the ADP2138/ADP2139 as possible.

2

SW

Switch Node Output. SW is the drain of the P-channel MOSFET switch and N-channel synchronous rectifier.

Connect the output LC filter between SW and the output voltage.

3

GND

Ground. Connect the input and output capacitors to GND.

4

EN

Buck Activation. To turn on the buck, set EN to high. To turn off the buck, set EN to low.

5

MODE

Mode Input. Drive the MODE pin high for the operating mode to force continuous PWM switching. Drive the MODE

pin low to allow automatic PWM/PSM operating mode.

6

VOUT

Output Voltage Sensing Input.