DN06003/D Design Note – DN06003/D 8 W, 3-Output Off-Line Switcher Device Application Input Voltage Output Power Topology I/O Isolation NCP1014 3 Output Power Supply for DVD Player 90 to 270 Vac 8W Flyback Yes - 3 kV I/O Other Specifications Output Voltage Ripple Nominal Current Max Current Min Current Output 1 Output 2 Output 3 Output 4 5V 100 mV 850 mA 1A 50 mA 12 V 120 mV 150 mA 200 mA 10 mA -28 V 250 mV 50 mA 50 mA 5 mA N/A PFC (Yes/No) No Minimum Efficiency 68 % Input Connector / Fuse 1 A fuse Operating Temp Range Cooling Method / Supply Orientation 0 to +50 °C N/A N/A N/A Convection Circuit Description Key Features An 8 watt, 3-output, isolated off-line switcher with universal AC input is presented here. The design is based around the NCP1014 monolithic, integrated controller. Utilization of the SOT-223 package for U1 is recommended for optimum thermal management. The power circuit design is a discontinuous mode flyback topology operating at 100 kHz, although the T1 magnetics design will allow for 65 kHz operation also. The output voltage configuration can be changed by altering the turns ratios of the secondaries if desired. Use of stacked windings for the 5 V and 12 V secondaries provides good regulation for both outputs. Voltage sensing and regulation is accomplished with simple zener diode and optocoupler circuit configuration. July 2006, Rev. 0 N/A • Low parts count, inexpensive off-line power supply for telecom, appliance or telecom applications. • Input EMI filter for agency compliance • Stacked 5 and 12 V transformer windings for improved cross regulation. • 8 watt output with 10 watt peak if SOT-223 package is used for NCP1014. • Ripple inductor for low ripple on 5 V output. • Over current and overvoltage protection. www.onsemi.com 1 DN06003/D Schematic F1 1A L1 90 270 Vac C1 C2 0.1 R2 "X" 0.1 "X" R1 7.5, 2W 1M 0.5W D1 - D4 1N4006 4 C4 1.5nF 3kV C3 47uF 400V T1 6 MBRS160 C8 L2 330 4.7uH 16V D7 5 D8 R3 68K 1W R7 C11 MBR140 C10 470, 6.3V R8 68 8.2K 100V 7 D5 MUR160 12V, 150 mA 1K C9 0.1 C12 0.1 C14 0.1 C13 8 D6 D9 3 1 5V, 850 mA Com -28V, 50 mA MURS120 1N4148 R4 510 2 C7 2.2 nF "Y" NCP1014 (SOT223 100 kHz) Z1 4.3V 1N5229B 3 R5 U1 4 2 4 1 + C5 10uf 25V U2 1 R6 200 C6 100pf 47 3 opto 2 Notes: 1. Crossed lines on schematic are not connected. 2. U2 is Vishay H11A817A optocoupler or equivalent. 3. L1 is Coilcraft BU16-4530R5BL or similar CM EMI inductor. 4. Z1 sets 5V output level (Vout = Vz + 0.85V) 5. U1 pin 4 tab should be soldered to clad for heatsinking. 6. See magnetics design for T1 details. July 2006, Rev. 0 www.onsemi.com Triple Output, 8 Watt, Off-line Power Supply based on NCP1014 Controller ON Semiconductor Design Group 2 DN06003/D 1 MAGNETICS DESIGN DATA SHEET Project / Customer: Triple output, off-line NCP1014 based power supply Part Description: Flyback transformer, 10W, 100 kHz, 3 output Schematic ID: T1 Core Type: 42515-EC or similar (Ae = 0.4 cm2) Core Gap: Gap for 1.2 mH on primary (pins 3 to 4) Inductance: 1.2 mH +/- 5% Bobbin Type: TBD (8 pin minimum) Windings (in order): Winding # / type Turns / Material / Gauge / Insulation Data Aux/Vcc winding (1 - 2) 9 turns of 32HN (0.25 mm dia) magnet wire evenly spiral wound over one layer with 3 mm end margins. Insulate for 1.5 kV to next layer. Primary (3 - 4) 88 turns of #32HN (0.25 mm dia) magnet wire over 2 layers with 44 turns per layer. Allow 3 mm end margins for both layers. Self-leads to pins and insulate for 3 kV to next winding. 12V secondary (6 - 5) 5 turns of #26HN (0.46 mm) wire spiral wound with 3 mm end margins. Self-leads to pins. 5V secondary (5 - 7) 4 turns of 0.46 mm wire spiral wound between the turns of the previous winding. Keep 3 mm end margins and insulate for 1 kV to next winding with tape. -28V secondary (7 - 8) 20 turns of #30HN ( 0.30 mm dia) wire spiral wound over previous winding with 3 mm end margins. Self-leads to pins. Tape insulate for 1 kV to next winding. Hipot: 3 kV from Vcc/primary to all secondaries. Lead Breakout / Pinout Schematic (Bottom view facing pins) 4 6 12V 5 5V Pri 3 7 Com 1 Vcc 2 8 -28V T.B.D. based on PCB layout. 1 © 2006 ON Semiconductor. Disclaimer: ON Semiconductor is providing this design note “AS IS” and does not assume any liability arising from its use; nor does ON Semiconductor convey any license to its or any third party’s intellectual property rights. This document is provided only to assist customers in evaluation of the referenced circuit implementation and the recipient assumes all liability and risk associated with its use, including, but not limited to, compliance with all regulatory standards. ON Semiconductor may change any of its products at any time, without notice. Design note created by Frank Cathell, e-mail: [email protected] July 2006, Rev. 0 www.onsemi.com 3