DatasheetsPDF.com

KA7540D

Samsung
Part Number KA7540D
Manufacturer Samsung
Description Simple Dimming Ballast Control IC
Published Apr 25, 2005
Detailed Description www.fairchildsemi.com KA7540 Simple Dimming Ballast Control IC Features • • • • • • • • Internal soft start No lamp pr...
Datasheet PDF File KA7540D PDF File

KA7540D
KA7540D

Overview
www.
fairchildsemi.
com KA7540 Simple Dimming Ballast Control IC Features • • • • • • • • Internal soft start No lamp protection Voltage controlled dimming 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 8-pin DIP & 8-pin SOP Descriptions The KA7540 provides simple and high performance electronic ballast control functions.
KA7540 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.
Voltage controlled dimming circuit is built into the IC to control the lighting output in a wide range.
Protection circuitry has also been added to prevent switches from burning out in no lamp condition.
Output gate drive circuit clamps power MOSFET gate voltage irrespective of supply voltage.
8-DIP Applications • Electronic Ballast • Lighting Control System • Half-bridge Drive Control System 1 8-SOP 1 Rev.
1.
0.
1 ©2001 Fairchild Semiconductor Corporation KA7540 Internal Block Diagram UVLO 2V Ref CS 6.
8µF 1 25µA VZ Vref − + 17µA VZ IS UVLO Internal bias 1.
8V + − 12.
5V 8 VCC Oscillator Ct 180pF 8Ict 2 Ict latch + Q + + IC 7 OUT 1 F.
D from VCS Vdim 3 80kΩ Vd 20kΩ 100µA 3pF VCC Id + − kVref VZ Frequency divider 6 OUT 2 Ldet 40kΩ 4 5pF 2V 25µA − + Shut down signal IS = 17µA × (Vref − VSS) / Vref Id = 25µA × (Vref − Vd) / Vref 5 GND IC Characteristics Parameter Initial soft start frequency Voltage controlled dimming KA7540 1.
33 × normal operating frequency 1 ~ 10V 2 KA7540 Pin Assignments CS 1 8 VCC Ct 2 7 OUT1 Vdim 3 6 OUT2 Ldet 4 5 GND (Top View) Pin Definitions Pin Number 1 2 3 4 5 6 7 8 Pin Name CS CT Vdim Ldet GND OUT 2 OUT 1 VCC Pin Function Description Soft start capacitor connection pin.
The pin voltage determines the phase of soft start, normal and dimming mode.
Timing capacit...


Similar Datasheet


@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site. (Privacy Policy & Contact)