Supertex inc. HV861DB1 Dimmable, Low Noise, Dual EL Lamp Driver Demoboard General Description The Supertex HV861DB1 demoboard contains all the necessary circuitry to demonstrate the features of the HV861 dual EL Lamp driver. Simply connect it to a power supply and a lamp as shown in Figure 1. A 2.2µF capacitor is connected between VREF and GND. It allows the lamp to slowly (in about 400ms) brighten up/dim down during power up/power down. The dimming feature is common to both lamps. Specifications Parameter Value VDD input voltage: 2.5V to 4.5V VIN inductor supply voltage: 3.2V to 4.2V Typical supply current: 28mA Lamp size: 4.5in2 Lamp frequency: 188Hz Converter frequency: 98kHz Board Layout VDD EL1 EN1 COM1 EN2 COM2 GND EL2 VIN Actual Dimensions: 26mm x 24mm Connections: EN1 and EN2: Lamp Selection CMOS logic inputs which enable/disable the lamp drivers. When EN1 is connected to VDD/GND, Lamp 1 (EL1) will be ON/OFF. When EN2 is connected to VDD/GND, Lamp 2 (EL2) will be ON/OFF. VDD: IC Supply Supplies the HV861 EL driver IC. The supplied circuit is optimized for 3.0V operation. VIN: Inductor Supply GND: Circuit Ground Connect to VDD and VIN negative terminals. Supply bypass capacitor for both VDD and VIN are provided on the demo board. External supply bypass capacitors are not necessary. EL1 and EL2: Lamp Connections Connects to Lamps 1 and 2. COM1 and COM2: Lamp Connections Connects to the other side of Lamps 1 and 2. Supplies the high voltage power converter. The demoboard is optimized for 3.2V to 4.2V operation Notes: All of the above connections must be made before powering up the supply voltages. The VREG pin should not be touched after power-up. Doc.# DSDB-HV861DB1 A032813 Supertex inc. www.supertex.com HV861DB1 Figure 1: HV861DB1 Circuit Schematic VIN = 3.2V to 4.2V 4.7µF 100µH Coilcraft LPS4012 BAS20 3.3MΩ 15 3 VDD = 3.0V 14 7 8 VREG VOUT LX CS VDD 2.0MΩ 1 REL-Osc 0.1µF HV861 COM1 2 RSW-Osc Input Logic Control: ON = 1.5V to VDD OFF = 0V to 0.2V 825kΩ 4 5 EL1 EL2 EN1 COM2 EN2 VREF PWM GND 16 13 6 2.2µF 3.3nF 100V NPO 12 11 EL1 9 10 EL2 Typical Performance Load size: EL1 = 10.8nF, EL2 = 9.3nF, total lamp size ~4.5in2 VDD (V) 3.0 3.0 3.0 3.0 3.0 Doc.# DSDB-HV861DB1 A032813 VIN (V) 3.2 3.6 3.8 4.0 4.2 Lamp IIN (mA) VCS (VPEAK) fEL (Hz) Lamp Brightness (cd/m2) EL1 EL2 14.6 - - 17.8 EL1 ON 21.3 EL2 ON 14.8 EL1 & EL2 ON 30.9 13.9 16.6 EL1 ON 18.8 14.7 - EL2 ON 12.8 - 17.9 EL1 & EL2 ON 27.5 14.4 17.4 EL1 ON 17.8 14.8 - EL2 ON 12.0 - 18.0 EL1 & EL2 ON 26.3 14.6 17.6 EL1 ON 16.9 14.8 - EL2 ON 11.4 - 18.0 EL1 & EL2 ON 25.0 14.6 17.7 EL1 ON 16.0 14.9 - EL2 ON 10.8 - 18.1 EL1 & EL2 ON 24.0 14.7 17.8 2 93 93 93 93 93 188 188 188 188 188 Supertex inc. www.supertex.com HV861DB1 Bill of Materials Component Description Package Manufacturer Part Number LX 100µH shielded inductor --- Coilcraft LPS4012-104MLB D1 200V fast recovery diode SOD-323 Diodes Inc. BAS20HT1 CIN 4.7µF, 10V ceramic chip capacitor 0805 Any --- CS 3.3nF, 100V, NPO chip capacitor 0805 NOVA CAP 0805N332K101NT CDD 0.1µF, 16V ceramic chip capacitor 0805 Any --- CREF 2.2uF, 16V ceramic chip capacitor 0805 Any --- REL 1% 2MΩ chip resistor 0805 Any --- RSW 1% 825kΩ chip resistor 0805 Any --- RREG 1% 3.3MΩ chip resistor 0805 Any --- RPWM 0Ω chip resistor 0805 Any --- 16-Lead QFN Supertex HV861K7-G U1 EL driver IC Note: The above circuit may be optimized further based on specification of the lamp used. Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives an adequate “product liability indemnification insurance agreement.” Supertex inc. does not assume responsibility for use of devices described, and limits its liability to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications refer to the Supertex inc. (website: http//www.supertex.com) Supertex inc. ©2013 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Doc.# DSDB-HV861DB1 A032813 3 1235 Bordeaux Drive, Sunnyvale, CA 94089 Tel: 408-222-8888 www.supertex.com