The ISL6731A and ISL6731B are active power factor

correction (PFC) controller ICs that use a boost topology. The

controllers are suitable for AC/DC power systems up to 2kW

and over the universal line input.

The ISL6731A and ISL6731B operate in Continuous Current

Mode (CCM). Accurate input current shaping is achieved with a

current error amplifier. A patent pending breakthrough

negative capacitance technology minimizes zero crossing

distortion and reduces the magnetic components size. The

small external components result in lower design cost without

sacrificing performance.

The internally clamped 12.5V gate driver delivers 1.5A peak

current to the external power MOSFET. The ISL6731A and

ISL6731B provide a highly reliable system that is fully

protected. Protection features include cycle-by-cycle

overcurrent, over power limit, over-temperature, input

brownout, output overvoltage and undervoltage protection.

The ISL6731A and ISL6731B provide excellent power

efficiency and transitions into a power saving skip mode

during light load conditions, thus improving efficiency

automatically. The ISL6731A and ISL6731B can be shut down

by pulling the FB pin below 0.5V or grounding the BO pin.

Two switching frequency options are provided. The ISL6731B

switches at 62kHz, and the ISL6731A switches at 124kHz.

Features

• Reduced component size requirements

- Enables smaller, thinner AC/DC adapters

- Choke and cap size can be reduced

- Lower cost of materials

• Excellent power factor and THD over line and load

- CCM mode with negative capacitance generator for

smaller EMI filter and improved performance

- Built-in current amplifier with flexibility of gain change

• Better light-load efficiency

- Automatic pulse skipping with programmable threshold

- Programmable or automatic shutdown

• Highly reliable design

- Cycle-by-cycle current limit

- Input average power limit

- OVP and OTP protection

- Input brownout protection

• Small 14 Ld SOIC package

Applications

• Desktop computer AC/DC adaptor

• Laptop computer AC/DC adaptor

• TV AC/DC power supply

• AC/DC brick converters