POWER MANAGEMENT

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SC4614

500kHz Voltage Mode PWM Controller

Features

Applications

January 16, 2007

Typical Application Circuit

Description

The SC4614 is a high-speed, voltage mode PWM con-

troller that provides the control and protection features

necessary for a synchronous buck converter.

The SC4614 is designed to directly drive the top and

bottom MOSFETs of the buck converter. It allows the con-

verter to operate at 500kHz switching frequency with

4V to 25V power rail and as low as 0.5V output. It uses

an internal 8.2V supply as the gate drive voltage for mini-

mum driver power loss and MOSFET switching loss.

The SC4614 features soft-start, supply power under volt-

age lockout, and hiccup mode over current protection.

The SC4614 monitors the output current by using the

Rdson of the bottom MOSFET in the buck converter that

eliminates the need for a current sensing resistor. The

SC4614 is offered in a MSOP-10 package.

voltages

shoot-through protection for MOSFETs

12V IN

1

2

1.5V OUT

SC4614

1

2

3

4

7

8

9

10

5

6

BST

OCS

COMP

FB

VCC

DL

PN

DH

GND

DRV

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