BF1556 For 5V1A Charger Design

Transcription

1 BF1556 For 5V1A Charger Design

2 Table of Contents BF1556 for High efficiency Charger Design: (AC Input Vac,Output 5V 1A, No-Load Standby Power <100mW, Meet Level VI efficiency) 1. Introduction Design Features Power Supply Design Specification 4 4. Schematic PCB Layout Bill of Materials Transformer Drawing Efficiency CV and CC Regulation Output Ripple Voltage Turn-on Delay Time Output Rise Time Dynamic Load Response MoU Common Mode Noise Vce Waveform Thermal Test Conducted EMI Radiated EMI

3 1. Introduction This document provides a reference design for a universal AC input, 5V 1A isolated fly-back adapter. For this design the BF1556 is used. It contains the complete specification of the power supply, a detailed circuit diagram and PCB layout, the entire bill of materials required to build the power supply, drawing of the power transformer, and test data of the most important performance. PCB Top view PCB Bottom view Figure 1 Circuit Board Photograph -2-

4 2. Design Features AC input range Vac DC output 5V 1A Meet 100mW no-load standby power consumption requirement Meet Level VI Efficiency requirement at end of USB Max ripple < 80mV Meet USB3.0 Dynamic Load Response Requirement -3-

5 3. Power Supply Design Specification The table below represents the minimum acceptable performance of the design. CV CC Description Input Voltage Line Frequency Standby Power Symbol Min Type Max Units Comment Vin 90 / 264 Vac / f 47 50/60 63 Hz / / / / 100 mw 230Vac Output Voltage Vout_cv V Measured at end of USB Output Current Iout_cv 0 / 1.2 A / Output Voltage Vout_cc 2 / / V / Output Current Iout_cc 1 / 1.2 A / Ripple&Noise Continuous Output Power Over Current Protection Active Mode Efficiency Turn-on delay time Hold up time Conducted/Radiation EMI Safety ESD Ambient Temperature Input Section Output Characteristics Vripple / / 80 mv Measured at end of USB Iout=1A 20MHz Bandwidth Pout / 5 / W / Iout_max / / 1.2 A Auto-restart η 73.6 / / % Time sequence Measured at end of USB Vin=115Vac&230Vac / / / 2 S Full load / 10 / / ms Full load Environmental Meets CISPR22B/EN55022B Meets IEC950,UL1950,Class Ⅱ / 15 / / KV / TAMB -5 / 45 Free convection,sea level -4- / /

6 4. Schematic D4 SB340 FR1 10Ω MB8S + C1 6.8uF L1 330uH L2 1.5K C2 3.3uF + R8 2M R9 2M C6 470pF R4 300K R7 300Ω D3 FR C3 470uF + C4 270uF + R10 1.5K 5 R5 22Ω D2 1N VDD C R3 56KΩ R2 17.4KΩ R1/C7 33pF C5 4.7uF 1 VFB 4 E 3 CS R6 1.5Ω IC1 BF1556 C 6 GND 7 CY1 100pF -5-

7 5.PCB Layout PCB Top PCB Bottom -6-

8 6. BOM Item Designator Description Qty 1 C1 E-Capacitor 6.8uF/400V 8* ±20% 1 2 C2 E-Capacitor 3.3uF/400V 6* ±20% 1 3 C3 E-Capacitor 470uF/10V 5* ±20% 1 4 C4 S-Capacitor 270uF/6.3V 5*7 105 ±20% 1 5 C5 SMD Capacitor 4.7uF/50V 105 ±20% C6 SMD Capacitor 470pF/250V 105 ±20% R1 SMD Capacitor 33pF/50V 105 ±20% R2 SMD Resistor K ±1% 1 9 R3 SMD Resistor K ±1% 1 10 R4 SMD Resistor K ±5% 1 11 R5 SMD Resistor R ±5% 1 12 R6 SMD Resistor R ±1% 1 13 R7 SMD Resistor R ±5% 1 14 R8 R9 SMD Resistor M ±5% 2 15 R10 SMD Resistor K ±5% 1 16 BD1 MB8S 1A800V MBS 1 17 D2 1N4007 1A1KV SOD D3 FR107 1A1KV SOD D4 SB340 3A/40V SMB 1 20 L1 Fixed inductor 330uH 5* L2 SMD 1.5K@300MHz IC1 PWM Controller IC BF1556 SOP FR1 Fuse Resistor 10R/1W 10% 1 24 T1 Transformer EE13 Lp=2.8mH 1 25 CY1 Y-Capacitor 100pF/250V 105 ±20% 1 26 Total 26-7-

9 7. Efficiency Regulation, Ripple and Efficiency Measurement * Note: Output voltage is measured at the end of PCB Vin (Vac) Pin (W) Iout (ma) Measure at the end of PCB Vout (V) Pout(W) η(%) / AVG η(%) F(KHz) V/ 50Hz / V/ 50Hz Europe COC Tier 2 Efficiency(%) :73.6(0.0834*LnPo *Po+0.609) -8-

10 8. Transformer drawing PRI SEC 1 HV DC+ 7 3F 5S 3S 1F 2S Triple Insulated Wires 0.50mm*1 9T-Secondary 2UEW 0.15mm*1 12T-Bias 2UEW 0.15mm*1 29T-Shield 2UEW 0.15mm*1 45T-Primary 2UEW 0.15mm*1 45T-Primary 2UEW 0.15mm*1 45T-Primary 2UEW 0.15mm*1 45T-Primary PS: 1. 磁芯接地, 即 PIN3; 2. 所有绕组靠边绕制 6F 7S Primary Bias Q-C VCC GND Electrica Spcifications: 180T 12T 9T -9- DC- Secondary 1.Primary Inductance(LP)=2.8±7%mH@10KHz; 2.primary Leakage Inductance 3.Core:EE13(Ferrite Material TDK PC40 or equivalent); 4.Bobbin:EE13; 5.Magnet wire : TYPE 2 - UEW(Primary),Triple Insulated Wires (Secondary); 6.HI-POT: PRI. TO SEC: AC3000V 5mA 3SEC SEC TO CORE: AC1500V 5mA 3SEC PRI. TO CORE: AC1500V 5mA 3SEC 6

11 9.CV and CC Regulation VI Curve (Vin=115Vac/60Hz) VOUT (V) IOUT (A) VI Curve (Vin=230Vac/50Hz) VOUT (V) IOUT (A) -10-

12 10. Output Ripple Voltage Vin=115V Full Load V=51mV Vin=230V Full Load V=52mV -11-

13 11. Turn-on Delay Time Vin=90V, Full Load T=1380mS Vin=264V, Full Load T=454mS -12-

14 12. Output Rise Time Vin=90V, Full Load T=16.40mS Vin=264V, Full Load T=15.60mS -13-

15 13. Dynamic Load Response Test Conditions: 1. Load: 0.1A-1.0A-0.1A; 3. Duty-Cycle: 50%; 2. Frequency: 200Hz; 4. Slew-Rate: 0.1A/us. Vin=90V Vo_max=5.280V Vo_min=4.670V Vin=264V Vo_max=5.290V Vo_min=4.70V -14-

16 14. MoU Test Conditions: 1. Vin=230Vac/50Hz; 2. Load: 5R Resistive Load; 3. The Length of Output DC-Cable: 1M; EPS Switching Frequency Component V_pp=1040mV -15-

17 15. Common Mode Noise Test Conditions: 1. Vin=230Vac/50Hz; 2. Load: 5R Resistive Load; 3. The Length of Output DC-Cable: 1M; V_pp= -61.6dB -16-

18 16. Vce Waveform Test Conditions: Vin=264Vac/47Hz; Io=1A Test Result: Vpeak=638V -17-

19 17. Thermal Test Note: The UUT is assembled with case and placed in a temperature chamber. Iout=1A Item Vin=90Vac T( ) Tr( ) PWM Controller(IC1,BF1556) Transformer Wire(T1,EE13) Transformer Core(T1, EE13) Schottky Diode(D4,SB340) Ambient Temperature 45 PCB Top view -18- PCB Bottom view

20 Amplitude(dBuV) Amplitude(dBuV) 18. Conducted EMI Vin=230Vac/50Hz, Neutral Frequency(MHz) Vin=230Vac/50Hz, Live Frequency(MHz) -19-

21 Amplitude(dBuV) 19. Radiated EMI Vin=230Vac/50Hz Frequency(MHz) -20-