DN06009/D Design Note – DN06009/D 5 W, CCCV Cell Phone Battery Charger Device Application Input Voltage Output Power Topology I/O Isolation NCP1014 Cell Phone Charger 90 to 270 Vac 5W Flyback Isolated Other Specifications Output Voltage Ripple Nominal Current Max Current Min Current Others Output 1 Output 2 Output 3 Output 4 5.0 V 200 mV p/p 1.0 A 1.1 A zero N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A PFC (Yes/No) No Minimum Efficiency 65% Operating Temp. Range Cooling Method/Supply Orientation 0 to +60°C Convection CCCV (Constant Current – Constant Voltage) output load profile for typical battery charger. Circuit Description Key Features This circuit presents a very simple, low cost, yet highly effective 5 watt, off-line constant current – constant voltage battery charger for cell phones or similar applications. The circuit is designed around ON’s NCP1014 integrated controller with internal mosfet in a discontinuous mode flyback topology. Current and voltage feedback are accomplished with a single optocoupler as well as providing ac mains isolation. The circuit provides a respectable output V/I load-line characteristic for battery charging over typical temperature variations. The use of an auxiliary Vcc winding on T1, although not required because of the 1014’s DSS circuitry, guarantees very low standby (no load) power consumption (< 300 mW). For maximum simplicity a half-wave input rectifier (D1) is utilized and a conducted EMI filter is provided by C1 and L1. If there are very low output line frequency ripple and/or low ac input constraints, a full bridge input rectifier is recommended. The T1 flyback transformer design is compliant enough for output voltage requirements from 4 to 6.5 volts. y Extremely simple yet effective off-line battery charger circuit. y Constant current – constant voltage output load line profile. y Less than 300 mW standby (no load) input power if auxiliary winding is used. y Conducted EMI input filter. y Adjustable output voltage and current with resistors. y Monolithic, integrated current mode controller with inherent over-current, over-temperature, and overvoltage protection. September 2006, Rev. 1 www.onsemi.com 1 DN06009/D Schematic AC input 1N4007 L1 T1 820uH 1 R1 C1 4.7nf "x" C2A 4.7uf, 400Vdc x2 C2B MBR350 7,8 C5 R2 1 nf 1 kV 150K C4 470uf 6.3V D3 Isense 0.68, 1W R7 1N914A 3 2N2907 D5 R8 R6 2K R5 2 4 4 5V@1A _ Q1 2 3 + Charger Output 0.1uf U1 C7 4 10 D4 NCP1014ST 10 nf 5,6 MUR160 C9 R4 D2 1 C6 U2 1 Jmpr Vtrim 47 R3 100pf + C3 10uf 25V 1N5229B D1 18, 2W 200 3 opto 2 NOTES: 1. Zener D5 and resistor R6 sets the output voltage. Vout = Vz + 0.9 volts approximately. Use R6 instead of a jumper to incrementally raise output voltage higher than Vz + 0.9 value. 2. R4 sets current limit threshold. I limit = 0.65/R4 3. Schematic shows "generic" passive component types. Surface mount parts may have different ID prefixes. 4. L1 is Coilcraft RFB0807-821L or similar (820 uH, 300 mA). NCP1014 Cell Phone Charger 5 Vout @ 1000 mA ON Semiconductor September 2006, Rev. 1 www.onsemi.com 2 DN06009/D MAGNETICS DESIGN DATA SHEET Project / Customer: ON Semiconductor - NCP1014 CC - CV battery charger Part Description: 5 watt flyback transformer, 4 - 6 volts out Schematic ID: T1 Core Type: EF16 (E16/8/5); 3C90 material or similar Core Gap: Gap for 3.5 mH inductance Inductance: 3.5 mH +/-5% Bobbin Type: 8 pin horizontal mount for EF16 Windings (in order): Winding # / type Turns / Material / Gauge / Insulation Data Vcc/Boost (2 - 3) 22 turns of #35HN spiral wound over 1 layer. Insulate with 1 layer of tape (500V insulation to next winding) Primary (1 - 4) 150 turns of #35HN over 3 layers. Insulate for 3 kV to the next winding. 5V Secondary (5, 6 - 7, 8) 10 turns of #24HN spiral wound over one layer with 0.050" (1.3mm) end margins. Triple insulated #24 can be subsituted without end margins. Vacuum varnish assembly NOTE: Existing vendor for this specific part is Mesa Power Systems, Escondido, CA. 1-800-515-8514 Hipot: 3 kV from boost/primary to secondary Lead Breakout / Pinout Schematic (Bottom View - facing pins) 1 8 7 4 4 6 5 3 2 1 5 6 7 8 3 1 2 © 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] September 2006, Rev. 1 www.onsemi.com 3