© Semiconductor Components Industries, LLC, 2012

January, 2012 − Rev. 0

1

Publication Order Number:

NCP1253/D

NCP1253

Current-Mode PWM

Controller for Off-line

Power Supplies

The NCP1253 is a highly integrated PWM controller capable of

delivering a rugged and high performance offline power supply in a

tiny TSOP−6 package. With a supply range up to 28 V, the controller

hosts a jittered 65 kHz or 100 kHz switching circuitry operated in peak

current mode control. When the power on the secondary side starts to

decrease, the controller automatically folds back its switching

frequency down to a minimum level of 26 kHz. As the power further

goes down, the part enters skip cycle while limiting the peak current.

To avoid sub harmonic oscillations in CCM operation, adjustable

slope compensation is available via the series inclusion of a simple

resistor in the current sense signal.

Besides the auto−recovery timer−based short−circuit protection, an

case of optocoupler destruction or adverse open loop operation.

Features

Operation

Conditions

Typical Applications

PIN CONNECTIONS

1

3

CS

GND

2

NC

4

DRV

6

(Top View)

TSOP−6

CASE 318G

STYLE 13

MARKING DIAGRAM

FB

http://onsemi.com

(Note: Microdot may be in either location)

1

53xAYWG

G

1

53

= Specific Device Code

x

= A, 2, C, or D

A

= Assembly Location

Y

= Year

W

= Work Week

G

= Pb−Free Package

See detailed ordering and shipping information in the package

dimensions section on page 2 of this data sheet.

ORDERING INFORMATION