© 2006 Fairchild Semiconductor Corporation

www.fairchildsemi.com

FAN7529 Rev. 1.0.2

3

Pin Assignments

Figure 3. Pin Configuration (Top View)

Pin Definitions

Pin #

Name

Description

1INV

This pin is the inverting input of the error amplifier. The output voltage of the boost PFC

converter should be resistively divided to 2.5V.

2COMP

This pin is the output of the transconductance error amplifier. Components for output

voltage compensation should be connected between this pin and GND.

3MOT

This pin is used to set the slope of the internal ramp. The voltage of this pin is main-

tained at 2.9V. If a resistor is connected between this pin and GND, current flows out of

the pin and the slope of the internal ramp is proportional to this current.

4CS

This pin is the input of the over-current protection comparator. The MOSFET current is

sensed using a sensing resistor and the resulting voltage is applied to this pin. An

internal RC filter is included to filter switching noise.

5ZCD

This pin is the input of the zero current detection block. If the voltage of this pin goes

higher than 1.5V, then goes lower than 1.4V, the MOSFET is turned on.

6GND

This pin is used for the ground potential of all the pins. For proper operation, the signal

ground and the power ground should be separated.

7OUT

This pin is the gate drive output. The peak sourcing and sinking current levels are

+500mA and -800mA respectively. For proper operation, the stray inductance in the

gate driving path must be minimized.

This pin is the IC supply pin. IC current and MOSFET drive current are supplied using

this pin.

FAN7529

6

5

8

7

V

CC

OUT

GND

ZCD

1

2

3

4

COMP

CS

MOT

INV

YWW

FAN7529 Rev. 00