DN-29 UC3842A Family - Frequency Foldback Technique Provides Protection

Texas Instruments

Published Date: 09/05/1999

Description

Excessive power dissipation can occur in switch-mode power supplies during startup and overload conditions. Many sophisticated PWM controllers provide the means for protection against these problems; however simple low-cost controllers require additional circuitry. This design note describes a circuit that uses only one additional resistor and transistor to enhance the performance of the UC3842A

Parts

Part Number Name Companion Part
5962-8670405XA 5962-8670405XA Buy Datasheet
5962-8670406PA 5962-8670406PA Buy Datasheet
5962-8670406XA 5962-8670406XA Buy Datasheet
5962-8670407PA 5962-8670407PA Buy Datasheet
TL3842D TL3842D Buy Datasheet
TL3842PE4 TL3842PE4 Buy Datasheet
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