New Products

BridgeSwitch Family of Integrated Half-bridges

August 30, 2020 by Power Integrations

The BridgeSwitch is a high-voltage, self-powered, half-bridge motor driver with integrated device protection and system monitoring.

The BridgeSwitch family of integrated half-bridges dramatically simplifies the development and production of high-voltage inverter driven single- or multi-phase PM or BLDC motor drives. It incorporates two high-voltage N-channel power FREDFETs with low and high-side drivers in a single small-outline package. The internal power FREDFETs offer ultra-soft and ultrafast diodes ideally suited for hard switched inverter drives. Both drivers are self-supplied eliminating the need for an external auxiliary power supply. BridgeSwitch provides a unique instantaneous phase current output signal simplifying the implementation of sensor-less control schemes. The low-profile, compact footprint surface mount package offers extended creepage distances and allows heat sinking of both power FREDFETs through the printed circuit board.


typical application schematic

Figure 1. Typical application schematic


BridgeSwitch offers internal fault protection functions and external system-level monitoring. Internal fault protection includes a cycle-by-cycle current limit for both FREDFETs and two-level thermal overload protection. External system-level monitoring includes DC bus sensing with four undervoltage levels and one overvoltage level as well as driving external sensors such as an NTC. The bi-directional bussed single-wire status interface reports observed status changes.


Product Highlights

Highest Performance and Design Flexibility

  • Fully integrated half-bridge stage with up to 98% efficiency
  • Eliminates external heat sink at rated continuous RMS current
  • 600 V N-channel power FREDFETs
  • Ultra-soft, fast recovery diode
  • Accurate instantaneous phase current information output (BRD126X)
  • Eliminates external sensing and amplification circuitry
  • Self-biased low-side and high-side drivers
  • Eliminates need for auxiliary power supply
  • Small footprint surface mount inSOP-24C package
  • Exposed pads enable heat sinking through PCB
  • Controlled FREDFET switching speed reduces EMI


Enhanced Safety and Reliability Features

  • Adustable cycle-by-cycle current limit for both FREDFETs
  • Fail-safe operation
  • UL test reports for BridgeSwitch: UL Informative Report IEC 60335-1 Safety of Household and Similar Electrical Appliances
  • Internal dual level thermal overload protection
  • Self-configuring system level monitoring input
  • Four level DC bus undervoltage
  • DC bus overvoltage
  • System temperature
  • Adaptive dead time
  • Simultaneous conduction lockout protection


Status Interface

  • Bi-directional bussed open Drain single wire interface
  • Reports status updates to system MCU
  • Successful power-up
  • Internal over-current or temperature faults
  • System level faults
  • Includes device identification
  • Status query through system MCU
  • Device fault reset through system MCU



  • Single- or multi-phase high-voltage PM and BLDC motor drives
  • Up to 400 W typical inverter output power
  • Appliances including dishwashers and refrigerators
  • Condenser fans in high-efficiency air conditioners