©2001 Fairchild Semiconductor Corporation

www.fairchildsemi.com

Rev. 1.0.3

Features

• Internal soft start

• Flexible soft start frequency

• No lamp protection

• Trimmed 1.5% internal bandgap reference

• Under voltage lock out with 1.8V of hysteresis

• Totem pole output with high state clamp

• Low start up and operating current

Descriptions

The KA7541 provides simple and high performance

electronic ballast control functions. KA7541 is optimized for

electronic ballast requiring a minimum board area, reduced

component count and low power dissipation. Internal soft

start circuitry eliminates the need for an external soft start

PTC resistor. The initial soft start switching frequency and

soft start time can be adjusted depending on the types of

lamps. Protection circuitry has also been added to prevent

burning out of switches in no lamp condition. output gate

drive circuit clamps power MOSFET gate voltage

irrespective of supply voltage

KA7541

Simple Ballast Controller

8-DIP

8-SOP

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