Analog Devices Inc. LT4322 Floating Active Rectifier Controllers

Analog Devices LT4322 Floating Active Rectifier Controllers are a device that drives an external N-Channel MOSFET to replace a rectifier diode. It is designed primarily for AC applications and operates with input supply frequencies ranging from DC to 100kHz. On each cycle of the input AC waveform, an external N-Channel MOSFET gate is enhanced to provide the equivalent of a low diode forward voltage drop of 25mV. The resulting reduction in power dissipation eliminates thermal design problems and costly heat sinks, greatly reducing PC board area.

The addition of a high-voltage depletion N-Channel MOSFET in the Analog Devices LT4322 enables operation at very high output voltages, limited only by the voltage ratings of two external MOSFETs. In AC applications, an integrated LDO provides the required gate drive voltage to turn the external MOSFET fully on. Fast, high-current gate drivers minimize reverse current transients at high input frequencies.


  • Replaces rectifying diodes with N-Channel MOSFETs in rectifier applications
  • Maximizes power efficiency, eliminates thermal design problems
  • Low 25mV forward voltage drop
  • 9V to > 500V wide operating voltage range
  • DC to 100kHz wide operating frequency range
  • Regulated 12V GATE drive for external N-Channel MOSFET enhancement
  • 8-Lead MSOP and 8-Lead, 3mm x 3mm, side wettable DFN packages


  • Single-phase, 3-phase, and 6-phase bridge rectifiers
  • Automotive alternator bridge rectifiers
  • Off-line active bridge rectifier
  • 3-phase aircraft power
  • High-voltage DC diode-OR with reverse blocking

Typical Application

Application Circuit Diagram - Analog Devices Inc. LT4322 Floating Active Rectifier Controllers
Published: 2023-05-03 | Updated: 2023-05-22