The PMP9649 reference design is a simple, low-cost high side Buck converter to convert universal AC input voltage (85Vac to 265Vac) to a non-isolated 20V/150mA DC output with UCC28720 controller. BJT is applied as the buck switch for cost optimization, and simplicity is achieved with bulit-in sample and hold regulation function in UCC28720.
Features
- Universal AC Input (85Vac to 265Vac)
- Simple, low cost solution with BJT employed as buck switch
- Small 14.6mm2 two layer PCB footprint with 24 BOM components (excluding test points)
- Greater than 77% full-load efficiency at high line
- Conducted EMI tested (confirms EN550022 and CISPR-22 Class B)