HV9912DB1 Supertex, HV9912DB1 Datasheet - Page 2

• Manufacturer Part Number: HV9912DB1
• Description: LED Lighting Development Kits HI BRIGHTNESS BOOST LED DRIVER DEMOBOARD
• Manufacturer: Supertex

Specifications of HV9912DB1

• Lead Free Status / Rohs Status: Supplier Unconfirmed

Testing The Demoboard
Normal Operation: Connect the input source and the output
LEDs as shown in the Connection Diagram and enable the
board. The LEDs will glow with a steady intensity. Connecting
an ammeter in series with the LEDs will allow measurement
of the LED current. The current will be 350mA +/- 5%.
Current Regulation: With the input power to the converter
disconnected, change the LED string voltage within
the specifications mentioned. The current output of the
HV9912DB1 will remain very steady over the entire load
range. Vary the input voltage while the circuit is operational.
The current will be regulated over the entire line range.
Open LED test: Connect a voltmeter across the output
terminals of the HV9912DB1. Start the demoboard normally,
and once the LED current reaches steady state, unplug
one end of the LED string from the demoboard. The output
voltage will rise to about 92V and the HV9912DB1 will shut
down. Once the LED string is reconnected, the driver will
start regulating current.
Short Circuit Test: When the HV9912DB1 is operating in
steady state, connect a jumper across the terminals of the
LED string. Notice that the output current will immediately
go to zero and the converter will shut down. Removing the
jumper will cause the HV9912DB1 to restart and continue to
regulate the LED current.
PWM Dimming: With the input voltage to the board
disconnected, apply a TTL compatible, push-pull square wave
signal between PWMD and GND terminals of connector J3
as shown in the Connection Diagram. Turn the input voltage
back on and adjust the duty cycle and/or frequency of the
PWM dimming signal. The output current will track the PWM
dimming signal. Note that although the converter operates
perfectly well at 1.0kHz PWM dimming frequency, the widest
PWM dimming ratio can be obtained at lower frequencies
like 100 or 200Hz.
Typical Results
1. Efficiency: The efficiency of the converter at various LED
string voltages are shown in Fig.1 (measured at the nominal
input voltage of 24V). Fig.2 shows the full load efficiency
of the converter at varying input voltages. The minimum ef-
ficiency of 93% for the converter occurs at 21V input and full
load output.
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1235 Bordeaux Drive, Sunnyvale, CA 94089
2
2. Current Regulation: Figs. 3 and 4 show the output cur-
rent regulation vs. output voltage and input voltage respec-
tively. The total current regulation (line and load combined)
is found to be less than 1%.
0.354
0.352
0.348
0.346
95
94
93
92
91
90
95
94
93
92
91
90
0.354
0.352
0.348
0.346
0.35
0.35
Fig. 3 Output Current vs. Output Voltage
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20
Fig. 4 Output Current vs. Input Voltage
20
35
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Fig. 1 Efficiency vs. Output Voltage
Fig. 2 Efficiency vs. Input Voltage
Tel: [phone]
40
40
45
22
45
22
50
Output Voltage (V)
Input Voltage (V)
50
Output Voltage (V)
Input Voltage (V)
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www.supertex.com
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24
24
60
60
HV9912DB1
65
65
26
26
70
70
75
75
28
80
28
80