Universal, Off-Line, High Brightness, 30mA LED Driver Demo Board HV990BDB General Description The Supertex HV990BDB demo board is a High- Brightness LED power driver to supply a string of LEDs using the HV990B IC from a universal AC input voltage. The HV990BDB can supply a maximum output current of 30mA to drive 0-40V LED strings from a wide input voltage - 90 to 6VAC, 0/60Hz. The power conversion stage of the HV990BDB consists of a diode bridge rectifier followed by a current-controlled buck converter operating at a switching frequency of 0kHz. The nominal output current of the demo board can be adjusted to any value between 30 and 30mA using the on-board trimming potentiometer. PWM dimming can be achieved by applying a pulse-width-modulated square wave signal between the PWMD and GND pins. Zero output current can be obtained only by PWM dimming. The HV990BDB is not CISPR- compliant. Additional filtering is required to make the board meet CISPR- limits. Specifications Parameter Input voltage Output voltage Output current Output current ripple (typ) @0V input Full load efficiency Power factor Input current (rms) Input current THD Switching frequency (typ) Minimum output current Open LED protection Output short circuit protection Dimensions Value 90-6Vrms, 0/60Hz 0-40V 30mA max % (peak-peak) @40V output, 30mA 88% @0VAC 86% @30VAC 0.70 @0VAC 0.48 @30VAC 0.0A @0VAC 0.4A @30VAC 94% @0VAC 9% @30VAC 0kHz 0mA @0VAC 30mA @30VAC yes no 68.6mm X 49.6mm Connection Diagram 0-40V, 30mA max. 90-6VAC 0/60Hz WARNING!!! Do not connect earth-grounded test instruments. Doing so will short the AC line, resulting in damage to the instrument and/or the HV990BDB. Use floating high voltage differential probes or isolate the demoboard by using an isolating transformer. There is no galvanic isolation. Dangerous voltages are present when connected to the AC line.
HV990BDB Connections PWM Dimming.. 3. 4. Connect the input AC voltage between the AC IN terminals as shown in the connection diagram. Connect the LED string between LED+ (anode of LED string) and LED- (cathode of LED string). Connect the PWMD terminal to the VDD terminal using the jumper provided to enable the LED driver. The current level can be adjusted using the on-board potentiometer. The HV990BDB is capable of being PWM dimmed by applying a square wave TTL compatible signal between PWMD and GND terminals. However, since there is no galvanic isolation on the board, care must be taken to prevent damage to the PWM dimming source and/or the HV990BDB. One simple way is to isolate the LED driver from the AC line using an isolation transformer. Another approach is to use an opto-isolator to drive the PWMD pin as shown in the figure below..0v square wave signal (<.0kHz) 3.8kΩ VDD Opto-isolator (eg: LTV-84 from Lite-On) PWMD Typical Results 90 Efficiency vs.input Voltage 90 Efficiency vs. LED String Voltage 8 40V output 8 0VAC Input Efficiency (%) 80 7 70 0V output Efficiency (%) 80 7 70 30VAC Input 6 6 60 80 30 80 30 80 Input Voltage (VAC) 60 0 0 0 30 40 0 LED String Voltage (V) 0 Current Regulation vs. Input Voltage 0 Current Regulation vs. LED String Voltage % change in 0-0V Output 40V Ouput % change in 0 0VAC Input 30VAC Input -0 80 30 80 30 80 Input Voltage (VAC) 0 0 0 0 30 40 0 LED String Voltage (V)
HV990BDB Waveforms Steady State waveforms at 0VAC input and full load output Steady State waveforms at 30VAC input and full load output Steady State waveforms at 90VAC input and 40V, 30mA output Steady State waveforms at 30VAC input and 0V, 30mA output 3
HV990BDB Silk Screen 4
HV990BDB Schematic Diagram J D STTHR06U L 4.7mH RL-9-4700 R6 0.6 R 464K 4 8 4 C3 t RT CL-40 0.uF, 30VAC uf, 400V 0.47uF, 400V Gnd Vin Rosc HV990 Gate CS U Vdd HD EN 3 9 R k R 78K C6 R7 K.uF, 6V 0.uF 0.47uF, 400V C Q STD7NM0N R4 k C7 00pF J3C 3 J3B J3A R3 K C8 C POS NEG U AC AC F A, 0VAC C4 J
Bill of Materials Item # Qty RefDes Description Package Manufacturer HV990BDB Manufacturer s Part Number C µf, 400V electrolytic capacitor Radial Nichion UVRG0MHD C3,C 0.47µF, 400V metal film capacitor Radial EPCOS Inc B3C6474K 3 C4 0.µF, 30VAC EMI suppresion capacitor Radial EPCOS Inc B39C304M 4 C6 0.µF, 6V X7R ceramic chip capacitor SMD080 Panasonic ECJ-VBC04K C7 00pF, 0V C0G ceramic chip capacitor SMD080 TDK Corp C0C0GH0J 6 C8.µF, 6V X7R ceramic chip capacitor SMD080 TDK Corp C0X7RCK 7 D 600V, A ultrafast diode SMB ST Micro STTHR06U 8 F A, 0VAC time lag fuse Radial Cooper Bussman SR--A-BK 9 H C/W DPAK heatsink SMT Aavid 706PD 0 J,J position, 0.6 pitch, vertical header Thru-Hole Molex 6-48-0 J3 3 position, 0.00 pitch, vertical header Thru-Hole Molex -03-03 L 4.7mH, 400mA rms, 470mA sat inductor Axial Renco USA RL-9-4700 3 Q 0V, 0.7Ω N-channel FET DPAK ST Micro STDNM0 4 RT 0Ω NTC inrush limiter Thru-Hole GE Sensing CL-40 R 464KΩ, /8W, % chip resistor SMD080 --- --- 6 R 78KΩ, /8W, % chip resistor SMD080 --- --- 7 R3 KΩ top adjust trimpot SMT Bourns Inc 336P--0G 8 3 R4,R,R7 KΩ, /8W, % chip resistor SMD080 --- --- 9 R6 0.6Ω, /4W, % chip resistor SMD06 --- --- 0 U 400V, A single phase diode bridge DF-S Diodes Inc DF04S U Universal LED Driver SO-6 Supertex HV990BNG-G 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. 009 All rights reserved. Unauthorized use or reproduction is prohibited. 0309 6 3 Bordeaux Drive, Sunnyvale, CA 94089 Tel: 408--8888 www.supertex.com