MC34261

MC33261

SEMICONDUCTOR

TECHNICAL DATA

POWER FACTOR

CONTROLLERS

PIN CONNECTIONS

Order this document by MC34261/D

D SUFFIX

PLASTIC PACKAGE

CASE 751

(SO–8)

8

1

8

1

P SUFFIX

PLASTIC PACKAGE

CASE 626

Voltage Feedback

Input 1

2

3

4

8

7

6

5

(Top View)

Compensation

Multiplier Input

Current Sense

Input

VCC

Drive Output

Gnd

Zero Current

Detect Input

Device

Operating

Temperature Range

Package

ORDERING INFORMATION

MC34261D

MC34261P

TA = 0° to +70°C

SO–8

Plastic DIP

MC33261D

MC33261P

SO–8

Plastic DIP

TA = – 40° to +85°C

1

MOTOROLA ANALOG IC DEVICE DATA

Power Factor Controllers

The MC34261/MC33261 are active power factor controllers specifically

designed for use as a preconverter in electronic ballast and in off–line power

converter applications. These integrated circuits feature an internal startup

timer, a one quadrant multiplier for near unity power factor, zero current

detector to ensure critical conduction operation, high gain error amplifier,

trimmed internal bandgap reference, current sensing comparator, and a

totem pole output ideally suited for driving a power MOSFET.

Also included are protective features consisting of input undervoltage

lockout with hysteresis, cycle–by–cycle current limiting, and a latch for single

pulse metering. These devices are available in dual–in–line and surface

mount plastic packages.

Simplified Block Diagram

Voltage

Feedback

Input

Multiplier,

Latch,

PWM,

Timer,

&

Logic

Vref

Error Amp

Multiplier

Undervoltage

Lockout

2.5V

Reference

Zero Current Detector

5

8

6

7

4

3

2

1

Drive Output

Gnd

Zero Current

Detect Input

Multiplier

Input

Compensation

VCC

Current Sense

Input

© Motorola, Inc. 1996

Rev 1