Power Factor Correction Controllers

Product Status: Mass Production


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.


  • 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


 Block Diagram


Basic Information
Production Status
Mass Production
UVLO Falling (V)
UVLO Rising (V)
Supply Current Icc
3.7 mA
Standby Current Max
.295 mA
Peak Output Current IPK
1.5 A
Min Duty Cycle (%)
Max Duty Cycle (%)
Switching Frequency (kHz)
Qualification Level
Temperature Range
-40 to +125

Action Needed