© Semiconductor Components Industries, LLC, 2002

October, 2002 – Rev. 8

1

Publication Order Number:

CS51033/D

CS51033

Fast PFET Buck Controller

The CS51033 is a switching controller for use in dc–dc converters.

It can be used in the buck topology with a minimum number of

external components. The CS51033 consists of a 1.0 A power driver

for controlling the gate of a discrete P–channel transistor, fixed

frequency oscillator, short circuit protection timer, programmable Soft

Start, precision reference, fast output voltage monitoring comparator,

and output stage driver logic with latch.

The high frequency oscillator allows the use of small inductors and

output capacitors, minimizing PC board area and systems cost. The

programmable Soft Start reduces current surges at start up. The short

circuit protection timer significantly reduces the PFET duty cycle to

approximately 1/30 of its normal cycle during short circuit conditions.

The CS51033 is available in an 8–Lead SO package.

Features

°C to 85°C

°C to 70°C

95 Units/Rail

http://onsemi.com

PIN CONNECTIONS

A

= Assembly Location

WL, L

= Wafer Lot

YY, Y

= Year

WW, W = Work Week

SO–8

D SUFFIX

CASE 751

1

8

1

51033

ALYW

8

MARKING

DIAGRAM

GND

CS

PGND

1

Device

Package

Shipping

ORDERING INFORMATION*

CS51033YD8

SO–8

95 Units/Rail

CS51033YDR8

2500 Tape & Reel

CS51033GD8

SO–8

SO–8

*Additional ordering information can be found on page

9 of this data sheet.

CS51033GDR8

2500 Tape & Reel

SO–8