PMP9074 Reference Design

Texas Instruments

85 to 265VAC Input 12V/5W Low Cost Flyback with BJT Reference Design


This 12V/5W reference design is optimized for very low cost and yet maintains good efficiency. Two key factors for minimizing cost are a BJT is used for the main power switch, and primary-side regulation eliminates the need for an optocoupler. The UCC28720 quasi-resonant flyback controller is able to implement both of these features. With quasi-resonant switching, efficiency at full load is over 80%, even with a BJT switch. Light-load losses are kept below 100mW due to burst mode operation.


Part Number Name Companion Part
UCC28720 UCC28720 Buy Datasheet

Bill Of Materials

Download the bill of materials for PMP9074 Download

Other Documents

Title Updated Type Size (KB)
PMP9074 PCB 03 Oct 2013 PDF 279
PMP9074 Gerber 03 Oct 2013 ZIP 171
PMP9074 BOM 03 Oct 2013 PDF 81
PMP9074 Schematic 03 Oct 2013 PDF 126