This board is a compact, 30-V DC, 400-W reference design for avionics applications, working with mains frequency between 400 Hz and 800 Hz. A two-phase interleaved transition mode (TM) power factor correction (PFC) based on the UCC28064A is used to correct power factor and at the same time to minimizes harmonic content of input current. The DC/DC is implemented employing the HB-LLC stage, using UCC256404 device. The efficiency is further improved by using synchronous rectification on the secondary side.

The reference design PMP31179 Rev_A was built on the PMP30763 Rev_D PCB.

• Maximum 400-W output power at 96 VAC–134 VAC grid connection
• Two-stage converter achieving 92.8% plug-to-plug efficiency:
  • First stage: PFC interleaved Boost (97% efficiency) with UCC28064A, allows reduced EMI filter size and increases efficiency
  • Second stage: half-bridge resonant LLC converter (95% efficiency) isolates HV input, and supplies 30 V, 13.3 A
• No need of an auxiliary power supply, since the second stage provides the bias voltage for the PFC
• Specifically designed to comply with DO160-G harmonic limits in avionics applications for mains frequency in the 400 Hz–800 Hz range

• Aircraft cockpit display
• Power conversion system (PCS)

Top of Board

Bottom of Board

Block Diagram

• 0–150 VAC, 400 Hz–800 Hz (minimum current limit 7 A_RMS), AC constant voltage source (VS1)
• Electronic load, (constant current range 0–15 A)
• Oscilloscope (minimum 100-MHz bandwidth)
• Current probe (minimum 100-kHz bandwidth)
• Optional: infrared camera

The board dimensions are 218.44 mm x 102.26 mm, height 31.75 mm (transformer T1).