CS1601

DS931PP6

3

2. PIN DESCRIPTION

CS

P FC Current S ens e

IFB

Link V oltage S ense

ZCD

P FC Zero-current Detect

GND

Ground

GD

P FC Gate Driver

VDD

IC S upply V oltage

STBY

S tandby

IAC

Rectifier V oltage S ense

4

3

2

1

5

6

7

8

8-lead S OIC

Figure 2. CS1601 Pin Assignments

Pin Name

Pin #

I/O

Description

IFB

1IN

Link Voltage Sense — A current proportional to the output link voltage of the PFC is

input into this pin. The current is measured with an ADC.

STBY

2IN

Standby — A voltage below 0.8V puts the IC into a non-operating, low-power state.

The input has an internal 600k

IAC

3IN

Rectifier Voltage Sense — A current proportional to the rectified line voltage is input

into this pin. The current is measured with an ADC.

CS

4IN

PFC Current Sense — The current flowing in the PFC MOSFET is sensed through a

resistor. The resulting voltage is applied to this pin and digitized for use by the PFC

computational logic to limit the maximum current through the power FET.

ZCD

5IN

Zero-current Detect— Boost Inductor demagnetization sensing input for zero-current

detection (ZCD) information. The pin is externally connected to the PFC boost inductor

auxiliary winding through an external resistor divider.

GND

6PWR

Ground — Common reference. Current return for both the input signal portion of the IC

and the gate driver.

GD

7OUT

PFC Gate Driver — The totem pole stage is able to drive the power MOSFET with a

peak current of 0.5A source and 1.0A sink.

8PWR

IC Supply Voltage — Supply voltage of both the input signal portion of the IC and the

gate driver. A storage capacitor is connected on this pin to serve as a reservoir for oper-

ating current for the device, including the gate drive current to the power transistor. This