Supertex inc. HV860DB1 Low Noise, Dimmable EL Lamp Driver Demoboard General Description Specifications The Supertex HV860DB1 demoboard contains all necessary Parameter Value circuitry to demonstrate the features of the HV860 EL lamp driver. Input voltage: 2.4 to 4.5V VIN inductor supply voltage: 5.5V Simply connect it to a power supply and a lamp as shown in Figure1. For EL lamp dimming, either a potentiometer or an n- Typical supply current: 10mA channel open drain PWM signal can be used, but not both. 2 Lamp size: 3.5in The potentiometer is used as a variable voltage divider to Lamp frequency: 200Hz change the voltage at the VREG pin. The V is voltage divided REF Converter frequency: 150kHz to change the V voltage thereby changing the V voltage. REG CS The V voltage amplitude, and thereby the lamp brightness, CS increases when the potentiometer is rotated counter-clockwise, and the lamp brightness decreases when it is rotated clockwise. Board Layout and Connection Diagram EN VA HV860DB1 R EL VDD VB R DIM R SW C DD C DIM PWM R PWM C C IN S Potentiometer D L X VIN GND Actual Dimensions: 20mm x 25mm Connections: EN - (Enable Input) effective voltage on the V pin is changed. This changes the V REG CS A CMOS logic input which enables/disables the lamp driver. A logic voltage, and hence the lamp brightness. The higher the duty cycle, high (1.5V) enables the driver and a logic low (connect to GND) the higher the lamp brightness, and vice versa. disables the driver. VA and VB - (Lamp Connections) VDD - (IC Supply) They connect to the EL lamp terminals. Polarity is irrelevant. Supplies the HV860 EL driver IC. The supplied demo board is op- timized for 3.0V operation, with an operating range from 2.4V to VIN - (Inductor Supply) 4.5V. It connects to the positive terminal of a power supply. Supplies the high voltage power converter. The demo board is op- timized for 5.5V operation. It connects to the positive terminal of a PWM - (PWM Input) power supply. Supplies the PWM signal for dimming the EL lamp. The frequency of this signal can vary between 20kHz and 100kHz. For EL lamp GND - (Circuit Ground) dimming using the PWM input, either the potentiometer has to be Connect to VDD and VIN negative terminals. Supply bypass ca- removed or its value set to for maximum lamp brightness. pacitor for both VDD and VIN are provided on the demo board. External supply bypass capacitors are not required. The n-channel open drain PWM signal pulls the 10k resistor to ground. When the duty cycle of this PWM signal is changed, the Note: All of the above connections must be made before powering up the supply voltages. The V pin should not be touched after power-up. REG Doc. DSDB-HV860DB1 Supertex inc. A032813 www.supertex.comHV860DB1 Figure 1: Circuit Schematic + C V IN IN 4.7F Cooper Inductor 2 10k 1 - SD3114-221, 220H 2M 3.3M Potentiometer 3 3.3nF, 2 3 5 n-channel Open Drain PWM signal BAS20HT1 200V VREG VREF LX 1206 Package 7 VDD + CS 10 590k HV860K7 C V DD DD RSW-Osc 0.1F 12 - 9 VA REL-Osc 1 EL Lamp 2.0M 8 EN VB 11 GND ON = 1.5V 4 OFF = 0V Typical Performance The specific external components used in the circuit schematic are: L = 220H Cooper (SD3114-221), C = 3.3nF 200V NPO and the 2M potentiometer. X S Brightness Lamp Size V V I V f DD IN IN CS EL 2 (in ) (V) (V) (mA) (V) (Hz) ft-lm cd/m2 3.5 3.0 5.2 9.0 110 190 6.20 21.21 3.5 3.0 5.5 8.4 110 190 6.22 21.27 3.5 3.0 5.8 7.9 110 190 6.24 21.33 Bill of Materials Component Description Package Manufacturer Part Number L 220H inductor --- Cooper SD3114-221 X C 3.3nF, 200V, NPO chip capacitor 1206 Tecate CMC-200/332JN1206T S R 1%, 590k chip resistor 0603 Any --- SW R 1%, 2M chip resistor 0603 Any --- EL R 5%, 3.3M chip resistor 0603 Any --- DIM R 1%, 10k chip resistor 0603 Any --- PWM C Optional capacitor for dimming control --- --- --- DIM C 4.7F, 10V ceramic chip capacitor 0603 Any --- IN C 0.1F, 16V ceramic chip capacitor 0603 Any --- DD Diode 200V fast recovery diode SOD-323 Diodes Inc. BAS20HT1 POT 2M Potentiometer --- Bourns Inc. 3352T-205 U1 EL driver IC 12-Lead QFN Supertex HV860K7 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) 2013 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Supertex inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 Tel: 408-222-8888 Doc. DSDB-HV860DB1 A032813 www.supertex.com 2 100110