ADP2118

Rev. 0 | Page 6 of 24

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

NOTES

1. THE EXPOSED PAD SHOULD BE SOLDERED TO

AN EXTERNAL GROUND PLANE UNDERNEATH

THE IC FOR THERMAL DISSIPATION.

12

11

10

1

3

4

PVIN

SW

SW

9

SW

SYNC/MODE

TRK

2

FREQ

FB

TOP

VIEW

ADP2118

Figure 3. Pin Configuration

Table 4. Pin Function Descriptions

Pin No.

Mnemonic

Description

1

SYNC/MODE

Synchronization Input (SYNC). Connect this pin to an external clock between 600 kHz and 1.4 MHz to

synchronize the switching frequency to the external clock (see the Oscillator and Synchronization section for

details).

CCM/PFM Selection (MODE). When this pin is connected to VIN, PFM mode is disabled and the ADP2118 only

works in continuous conduction mode (CCM). When this pin is connected to ground, PFM mode is enabled

and becomes active at light loads.

2

FREQ

Frequency Selection. Connect to GND to select 600 kHz and VIN for 1.2 MHz.

3

TRK

Tracking Input. To track a master voltage, drive TRK from a voltage divider from the master voltage. If the

tracking function is not used, connect TRK to VIN.

4

FB

Feedback Voltage Sense Input. Connect to a resistor divider from V

to V

5

GND

Analog Ground. Connect to the ground plane.

6, 7, 8

PGND

Power Ground. Connect to the ground plane and to the output return side of the output capacitor.

9, 10, 11

SW

Switch Node Output. Connect to the output inductor.

12, 13

PVIN

Power Input Pin. Connect this pin to the input power source. Connect a bypass capacitor between this pin

and PGND.

14

VIN

Bias Voltage Input Pin. Connect a bypass capacitor between this pin and GND and a small (10 Ω) resistor

between this pin and PVIN.

15

EN

Precision Enable Pin. The external resistor divider can be used to set the turn-on threshold. To enable the part

automatically, connect the EN pin to VIN. This pin has a 1 MΩ pull-down resistor to GND.

16

PGOOD

Power-Good Output (Open Drain). Connect to a resistor to any pull-up voltage <5.5 V.

17 (EPAD)

Exposed Pad

The exposed pad should be soldered to an external ground plane underneath the IC for thermal dissipation.