HV9906DB2 Off-Line Current Source Controller Introduction The Supertex HV9906DB2 demo board contains all circuitry necessary to demonstrate the features of the HV9906 second order power supply controller. The power converter of the demo board consists of an input buck-boost stage and an output buck stage. The output voltage polarity is negative. Due to its unique quadratic input-to-output DC voltage transfer ratio, the converter can operate directly off AC line to produce low-voltage output without need for electrolytic capacitors. HV9906 is designed for optimal controlling this type of power converter or other types of two-stage multi-converters. The board is optimized for driving a 6V 400mA (700mA max.) LED. However, it may be modified to meet custom requirements. Specification Input Voltage 80 to 135VAC, 60Hz Output Current 400mA ±10% (700mA max.) Output Voltage 10V max. Efficiency 62% at Io=500mA, Vin=100VAC Board Layout and Connections WARNING!!! Do not connect to scope ground or to the ground of other earth-grounded instruments. Doing so will short the AC line, resulting in damage to the circuit and/or instruments. Either use an isolation transformer on the AC line, use a differential probe, or use a floating, battery-powered instrument to make measurements. WARNING!!! No galvanic isolation. Dangerous voltages are present when connected to the AC mains. 1 07/23/02 Supertex, Inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 TEL: (408) 744-0100 FAX: (408) 222-4895 www.supertex.com HV9906DB2 Instructions NEG, RTN (such as an oscilloscope) will short the AC line, resulting in circuit and/or instrument damage. Connect your LED to these terminals: negative to NEG, positive to RTN. Also note that GND may be at higher potential with respect to earth ground, even if the AC is switched off. Use caution! E1, E2 Connect 80 to 135VAC, 60Hz line source to these terminals: line to E1, neutral to E2. The input is protected with a 0.5A fuse. IMPORTANT: Make sure that your LED is connected to NEG and RTN terminals. There is no open circuit protection available in this demo board. Contact Supertex, Inc. for the application circuit if protection is required. Do not connect to earth-ground. Setting Output Current Output current is preset to 400mA for this board. Output current can be re-programmed according to the following equation: GND This is circuit common. Iout = Note that since galvanic isolation is not provided, connecting this point to an earth-grounded instrument R6 − R7 ⋅ 1V R 7 ⋅ R3 The average output current will come out 5-10% smaller due to power transfer interruptions during the AC line voltage cusps. Schematic Diagram D5 D6 L3 B1 D1 MURS160 D2 L2 0.033 C3 MURS120 100uH NEG F1 100uH E1 1/2A S 40 F D .1 C2 D7 R1 E2 M1 IRFR320 MURS120 22 D3 Q1 D4 LED1 LED MMBT2907 R4 976K R6 DUT 8 1 RTN 6 2 R5 121K C5 R7 0.1 3 HV9906 R3 .47 5 12.1K 100K 7 4 C6 10uF 2 GND 07/23/02 Supertex, Inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 TEL: (408) 744-0100 FAX: (408) 222-4895 www.supertex.com HV9906DB2 Parts List Item Reference Part Part Number Manufacturer Part No. 1 B1 Diode Bridge DF04S Diodes Inc. DF04S 2 C2 Cap, PEN Film 0.1uF 250V ECW-U2104KC9 Panasonic ECW-U2104KC9 3 C3 Cap, PEN Film 0.033uF 250V ECW-U2333KC9 Panasonic ECW-U2333KC9 4 C5 0.1 uF, 50V, 10% 5 C6 10 uF, 16V Tantalum Chip 6 D5 Diode, Ultra Fast, 600V 1A MURS160T3 On Semi MURS160T3 7 D6 Diode, Ultra Fast, 200V 1A MURS120T3 On Semi MURS120T3 8 D7 Diode, Ultra Fast, 200V 1A MURS120T3 On Semi MURS120T3 9 F1 Fuse, 1/2A, Slow Blow R452.500 Littelfuse R452.500 10 L2 100uH, 1.7A CTCDRH127-101 Central Technologies CTCDRH127-101 11 L3 100uH, 1.2A DO3316P-104 Coilcraft 12 M1 MOSFET, 400V IRFR320 International Rectifier IRFR320 13 Q1 BJT, PNP MMBT2907 On Semi MMBT2907 14 R1 22 ohm, 1%, 1/8W 15 R3 0.47 ohm, 1%, 1/4W 16 R4 976K ohm, 1%, 1/8W 17 R5 12.1K ohm, 1%, 1/8W 18 R6 121K ohm, 1%, 1/8W 19 R7 100K ohm, 1%, 1/8W 20 U1 PWM/PFM IC HV9906 Supertex, Inc. HV9906 DO3316P-104 3 07/23/02 Supertex, Inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 TEL: (408) 744-0100 FAX: (408) 222-4895 www.supertex.com The Supertex SuperNova Powers the Luxeon Star Highlights: - 400mA (700mA when potted) Small 25mm x 25mm x 11mm size High reliability No electrolytic capacitors Operates directly off AC line (85VAC<Vin<135VAC) Maintains regulation down to 20VDC input PCB Layout: Fig. 1 - Top view Fig. 2 – Bottom view Waveforms: Fig. 3 – Output Current (Vin = 120VDC) Fig. 4 – Output Current (Vin = 120AC) Waveform Summary: Fig. 3 shows continuous nature of the output current. Peak-to-average current ratio is close to unity. Fig. 4 shows that current drops out of regulation for short periods of time only during the AC line cusps. (Switching ripple component is attenuated for clarity.) Fig. 5 – Input Current and Voltage (Vin = 120VAC) Fig. 5 shows the input current nature. The converter delivers full output power to the output down to very low input voltage.