KA7541

KA7541 Datasheet

KA7541

Part	Datasheet
KA7541	KA7541 (pdf)

Related Parts	Information
KA7541DTF	KA7541DTF
KA7541D	KA7541D

PDF Datasheet Preview
KA7541 Simple Ballast Controller • Internal soft start • Flexible soft start frequency • No lamp protection • Trimmed 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 8-DIP 8-SOP 2001 Fairchild Semiconductor Corporation KA7541 Internal Block Diagram CS 0.22µF Ct 180pF 2.5µA VZ Vref IH 2 8Ict Ict + + 3V - R latch 3pF + 2V Ref Internal bias Ik = IS / 6 IC Oscilator Oscilator Current mirror Vref Ldet 4 5pF + Shut down signal UVLO 1.8V + UVLO − 9.5V 8 VCC Frequency divider VCC 6 IH = Ik x Vref − VSS / Vref IS = Vref / RS VCC OUT 1 OUT 2 GND Absolute Maximum Ratings Parameter Supply voltage Peak drive output current Drive output clamping diodes VO>VCC, or VO<−0.3 Soft start, and no lamp detection input voltage Operating temperature range Storage temperature range Ordering Information Product Number KA7541 KA7541D Package 8-DIP 8-SOP Operating Temperature -25°C ~ +125°C KA7541 KA7541 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: Life support devices or systems are devices or systems which, a are intended for surgical implant into the body, or b support or sustain life, and c whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. 9/27/01 0.0m 001 2001 Fairchild Semiconductor Corporation

PDF Datasheet Preview

KA7541

Simple Ballast Controller
• Internal soft start
• Flexible soft start frequency
• No lamp protection
• Trimmed 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
8-DIP
8-SOP
2001 Fairchild Semiconductor Corporation

KA7541

Internal Block Diagram

CS 0.22µF

Ct 180pF
2.5µA VZ

Vref IH
2 8Ict

Ict +
+ 3V -

R latch
3pF +
2V Ref Internal
bias

Ik = IS / 6 IC

Oscilator

Oscilator

Current mirror

Vref

Ldet 4
5pF +

Shut down signal

UVLO
1.8V +

UVLO
− 9.5V
8 VCC

Frequency divider

VCC 6

IH = Ik x Vref − VSS / Vref

IS = Vref / RS

VCC OUT 1 OUT 2 GND

Absolute Maximum Ratings

Parameter Supply voltage Peak drive output current Drive output clamping diodes VO>VCC, or VO<−0.3 Soft start, and no lamp detection input voltage Operating temperature range Storage temperature range
Ordering Information

Product Number KA7541 KA7541D

Package 8-DIP 8-SOP

Operating Temperature -25°C ~ +125°C

KA7541

KA7541

DISCLAIMER

FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.

LIFE SUPPORT POLICY

FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein:

Life support devices or systems are devices or systems which, a are intended for surgical implant into the body, or b support or sustain life, and c whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user.

A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness.
9/27/01 0.0m 001 2001 Fairchild Semiconductor Corporation

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Datasheet ID: KA7541 634127