Schematic for the NCP1075PSRGEVB Evaluation Board J1 L1A F1 1 mH 1.5A C1 AC Input T1 0.1uF "X" R1 4.7 ohms 3W R2A C2 0.1uF "X" L1B 3.3M D1-D4 MRA4007 X4 C3 R3 C4 68K 1/2W 1nF 1kV D5 22uF 400V U1 R2B 3.3M 1 mH Primary Ground Plane 4 1N4937 NCP1075 (100 kHz) J2 C9A C9B + 7,8 R4 MMSD 4148A R5 1K 22 C5 22uF 25V 4 D7 3 2 1 1 D6 C6 Q1 MBRS 260T3 Secondary Ground Plane 2 22uF 25V R6 120 0.1uF 50V 5,6 3 C10 12Vout Z2 C11 _ 1000uF, MMSZ 0.1uF 16V x 2 5245B 50V C8 1nF "Y1" C7 1nF NOTES: Z1 R7 MMSZ 5241B 680 1. Crossed schematic lines are not connected. 2. R4 value dependent on aux winding turns and Vout setpoint. 3. R1 is optional inrush limiting resistor. 4. U1 tab (pin 4) and D7 should have heatsinking clad pours. 5. Heavy lines indicate recommended ground plane areas. 6. L1A/L1B are Wurth 7447728102. 7. Q1 is MMBT2222A or similar. 8. Z1 sets Vout (Vout = Vz + 0.6V for Ns:Naux = 1:1). 9. R6 trims Vout (up only). 10. Z2 is optional no load OVP zener (Vz = Vout + 2V) 10 Watt NCP1075 Power Supply with Primary Side Sensing (Rev 1A) 4/7/2014 -1- www.onsemi.com