PMP21479 Reference Design

Texas Instruments

65W Active clamp flyback with Si FETs reference design for a high power density 5-20V AC/DC adapter


This reference design uses the UCC28780 active clamp flyback controller to generate a 20-V/15-V/9-V/5-V adjustable output voltage. The maximum power rating is 65 W at 20-V output and up to 3 A at all other output voltage settings. This design reaches a peak efficiency of over 93% using silicon FETs: due to zero voltage switching (ZVS) and recaputuring the leakage energy.  The high efficiency enables a small form factor and a high power density.

  • Zero voltage switching (ZVS) provides high efficiency (93.5% peak value)Low: no load power consumption (33 mW)Supports outputs of 5V/3A: 9V/3A: 15V/3A: and 20V/3.25AConducted emissions (EMI) data provided in test reportSmall size (48mm x 48mm x 25mm) provides high power density (18W/in^3)
Product Categories
  • Power management