Data Sheet

1.1MHz, 650mA SYNCHRONOUS DC-DC BUCK CONVERTER

AP3406

Oct. 2009 Rev. 1. 4

BCD Semiconductor Manufacturing Limited

2

EN

SW

GND

VIN

FB

1

2

34

5

Pin Configuration

KT/K Package

TSOT-23-5/SOT-23-5

Figure 2. Pin Configuration of AP3406 (Top View)

Pin Description

Pin

Number

Pin

Name

Function

1

EN

Control input pin. Forcing this pin above 1.5V enables the IC. Forcing this pin

below 0.6V shuts down the IC. When the IC is in shutdown mode, all functions

are disabled to decrease the supply current below 1

μA

2

GND

Ground pin

3

SW

Power switch output pin. Inductor connection to drain of the internal PFET and

NFET switches

4

VIN

Supply input pin. Bypass to GND with a 4.7

μF or greater ceramic capacitor

5

FB

Feedback pin. Connect it with an external resistor divider network to program

the system output voltage