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FAN7528 Rev. 1.0.1

Pin Assignments

Figure 3. Pin Configuration (Top View)

Pin Definitions

Pin Number

Pin Name

Pin Function 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 at the high line condition and connected to this pin. If this

pin voltage is controlled to be lower than 0.45V, the device is disabled.

2COMP

This pin is the output of the transconductance error amplifier. Some components for the 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 maintained to be

1V. 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. This pin is sensitive to the negative voltage below -0.3V. For

proper operation, the stray inductance in the sensing path and the inductance of the sensing re-

sistor must be minimized.

5ZCD

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

1.5V and 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 level is 400mA. For prop-

er operation, the stray inductance in the gate driving path must be minimized.

8

Vcc

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

FAN

7528

6

5

8

7

Vcc

OUT

GND

ZCD

1

2

3

4

COMP

CS

MOT

INV

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