Isolated Octo-output Fly-Buck Bias for IGBT Driver - Reference Design
The PMP10531 reference design is an 8-output isolated Fly-Buck power supply for IGBT gate driver in motor drive or high voltage inverter applications. It takes 24V nominal input and provides 4 isolated sets of (+15V: -8V) bias voltage. The board is designed to provide driver bias power for 6 IGBTs in 3-phase configuration: 3 sets of outputs for the 3 top side IGBTs with 100mA output current: and 1 set of 300mA outputs for all the bottom IGBTs. Each set of positive/negative rails is generated from one single transformer windings using voltage split circuit. A compact solution size is achieved (62x55mm). The design features the LM5160 synchronous buck converter configured as a Fly-Buck regulator. With the benefit of primary side regulation: the supply has the outputs regulated without the opto-coupler or additional transformer winding. The LM5160 has a wide Vin range of 4.5V to 65V and 1.5A output current capability with integrated switch FETs. The input voltage to the reference board can be loosely regulated with a range of 20V to 30V.
• Eight isolated outputs: 1x(+15V/-8V @ 300mA): 3x(+15V/-8V @ 100mA): ideal for 3-phase AC motor and inverter applications • Fly-Buck converter design: primary side regulation: compact solution for multiple isolated output supply• Wide input voltage range of 20V to 30V• Provides 2.3W supply power for each of the 6 IGBT drivers: 82% peak efficiency.• LM5160 sync buck regulator: up to 65V wide Vin range: 1.5A capability• This circuit board is tested: and the design files and test report are included.