© Semiconductor Components Industries, LLC, 2019

December, 2019 − Rev. 0

1

Publication Order Number:

FSDH321/D

Green Mode Power Switch

FSDH321, FSDL321

Description

Each product in the FSDx321 (x for H, L) family consists of an

integrated Pulse Width Modulator (PWM) and SENSEFET, and is

specifically designed for high performance offline Switch Mode

Power Supplies (SMPS) with minimal external components. Both

devices are integrated high voltage power switching regulators which

combine an avalanche rugged SENSEFET® with a current mode

PWM control block. The integrated PWM controller features include:

a fixed oscillator with frequency modulation for reduced EMI, Under

Voltage Lock Out (UVLO) protection, Leading Edge Blanking (LEB),

an optimized gate turn−on/turn−off driver, Thermal Shut Down (TSD)

protection, Abnormal Over Current Protection (AOCP) and

temperature compensated precision current sources for loop

compensation and fault protection circuitry. When compared to a

discrete MOSFET and controller or RCC switching converter

solution, the FSDx321 devices reduce total component count, design

size, weight while increasing efficiency, productivity and system

reliability. Both devices provide a basic platform that is well suited for

the design of cost−effective flyback converters.

Features

• Internal Avalanche Rugged SENSEFET

• Consumes only 0.65 W at 240 VAC & 0.3 W Load with Advanced

Burst−Mode Operation

• Frequency Modulation for EMI Reduction

• Precision Fixed Operating Frequency

• Internal Start−up Circuit

• Pulse−by−Pulse Current Limiting

• Abnormal Over Current Protection (AOCP)

• Over Voltage Protection (OVP)

• Over Load Protection (OLP)

• Internal Thermal Shutdown Function (TSD)

• Auto−Restart Mode

• Under Voltage Lockout (UVLO)

• Low Operating Current (max. 3 mA)

• Adjustable Peak Current Limit

• Built−in Soft Start

Applications

• SMPS for STB, Low Cost DVD Player

• Auxiliary Power for PC

• Adapter & Charger

www.onsemi.com

MARKING DIAGRAM

See detailed ordering and shipping information in the package

dimensions section on page 2 of this data sheet.

ORDERING INFORMATION

PDIP8

(9.42x6.38, 2.54P)

CASE 646CM

ZXYKK

Dx321

Z

= Assembly Code

XY

= 2−digit Code (Year & Week)

KK

= 2−digit Die−Run Code

Dx321 (x=H/L)

= Specific Device Code

PIN CONFIGURATION

8DIP

(Top View)

ON