BL9313

www.belling.com.cn

4

V1.0

PIN DESCRIPTION

Pin No.

Name

Description

1

BST

Boostrap pin for top switch. A 0.1uF or larger capacitor should be connected between

this pin and the SW pin to supply current to the top switch and top switch driver.

2

GND

Power ground pin.

3

FB

Output feedback pin. FB senses the output voltage and is regulated by the control loop

to 0.6V. Connect a resistive divider at FB.

4

EN

Drive EN pin high to turn on the regulator and low to turn off the regulator.

5

IN

Input voltage pin. VIN supplies power to the IC. Connect a 4.5V to 18V supply to VIN and

bypass VIN to GND with a suitably large capacitor to eliminate noise on the input to the

IC.

6

SW

SW is the switching node that supplies power to the output. Connect the output LC filter

from SW to the output load.

BLOCK DIAGRAM

+

-

+

0.6V

FB

+

-

+

-

+

Oscillator

Current

Ramp

CLK

Current

Sensor

-

Current

Sensor

+

Error

Amplifier

Current

Comparator

Logic

Control

3.3V LDO

+

-

EN

1.2V

VIN

BST

SW

GND

3.3V

Internal

SoftStart