Supertex inc.
HV9967BDB1
4W LED Driver Demoboard
with Accurate Average-Mode Constant Current Control
General Description
Specifications
The HV9967BDB1 demoboard is a high-brightness LED
driver designed to drive 4 LEDs in series at currents up to
350mA from a 20 - 60V DC input. The demoboard uses the
Supertex’s HV9967B in a buck configuration in a constant
off-time mode.
The HV9967BDB1 LED driver features tight regulation of the
LED current within a few milliamps over the entire range of
the input voltage (i.e. 20 - 60VDC). The LED current accuracy
is almost insensitive to the passive component tolerances,
such as the inductance or the timing resistor.
PWM dimming can be achieved by applying a pulse-widthmodulated square wave signal between the PWMD and
GND pins.
Parameter
Specification
Input voltage
20 - 60 VDC
Output voltage
10 -15VDC (4 x LEDs)
Output current
350mA ± 5%
Output current ripple
20% pk-pk
(Typical, depending on
the type of LED)
Switching frequency
Variable with constant
TOFF = 5µs ± 20%
Full load efficiency
Typical 80% minimum
Output short circuit protection
Included, hiccup mode
Connection Diagram
VLED (+)
VLED (-)
VIN (+) VIN (-)
VDD PWMD GND
Connections
1. Connect the LED string between LED+ (Anode of
LED string) and LED- (Cathode of LED string).
2. Connect the PWMD terminal to the VDD terminal
to enable the LED driver if PWM dimming is not required.
Doc.# DSDB-HV9967BDB1
B101613
3. Connect the input DC voltage between the VIN+
and VIN- terminals.
Supertex inc.
www.supertex.com
HV9967BDB1
Circuit Schematic
J1
1
2
C3
1.0µF
100V
C4
1.0µF
100V
R4 52k3 1%
6
J3
8
R2 1k0
3
2
1
4
7
C1
1.0µF
16V
J2
W3
JX;;89
TV
RYOF
330µH
TUGPUG
CIPF
2
1
L1
1
UY
XFF
C2
4.7µF
25V
D1
B1100
2
TP1
R1
0R68
1/4W
RIPF
3
TP2
Typical Characteristics
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0.38
0.36
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200
150
100
0.34
0.32
50
20
30
40
50
0.3
60
Kprwv"Xqnvcig"*X+
20
30
40
50
60
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90.0
88.0
86.0
20
30
40
50
60
Kprwv"Xqnvcig"*X+
Doc.# DSDB-HV9967BDB1
B101613
2
Supertex inc.
www.supertex.com
HV9967BDB1
Normal Operation:
Figures 1-4 show the waveforms during normal operation at loading of 4 x LED in series at different input.
Channel 4
Channel 1
Figure 1: 20V Output
Channel 1 (Brown)
:
Drain-Source Voltage (10V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
5µs/div
Channel 4
Channel 1
Figure 2: 30V Output
Doc.# DSDB-HV9967BDB1
B101613
Channel 1 (Brown)
:
Drain-Source Voltage (10V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
5µs/div
3
Supertex inc.
www.supertex.com
HV9967BDB1
Channel 4
Channel 1
Figure 3: 40V Output
Channel 1 (Brown)
:
Drain-Source Voltage (10V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
5µs/div
Channel 4
Channel 1
Figure 4: 60V Output
Doc.# DSDB-HV9967BDB1
B101613
Channel 1 (Brown)
:
Drain-Source Voltage (10V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
5µs/div
4
Supertex inc.
www.supertex.com
HV9967BDB1
PWM Dimming Operation:
PWM dimming operation at 4xLED in series with an external TTL square wave signal is shown in Figures 5 - 7. Figure 5
shows the overall operation of the circuit with PWM dimming input and Figures 6 and 7 show the rise and fall times of the
LED current during PWM dimming.
Channel 4
Channel 2
Figure 5: PWM Dimming at 24V PWMD Input
Channel 2 (Pink)
:
Drain-Source Voltage (2V/div)
Channel 4 (Green)
:
Output LED Current (100mA/div)
Time Scale
:
1ms/div
Channel 4
Channel 2
Figure 6: PWM Dimming at 24V - Rise Time
Doc.# DSDB-HV9967BDB1
B101613
Channel 2 (Pink)
:
Drain-Source Voltage (2V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
50µs/div
5
Supertex inc.
www.supertex.com
HV9967BDB1
Channel 4
Channel 2
Figure 7: PWM Dimming at 24V - Fall Time
Channel 2 (Pink)
:
Drain-Source Voltage (2V/div)
Channel 4 (Green)
:
Output LED Current (50mA/div)
Time Scale
:
50µs/div
Bill of Materials
Item#
Qty
Ref
Des
Description
Package
Manufacturer
Manufacturer’s
Part Number
1
1
C1
1µF 16V X7R
ceramic chip capacitor
SMD 0805
Murata
GRM21BR71C105KA88L
2
1
C2
4.7µF 25V X7R
ceramic chip capacitor
SMD 1206
Murata
GRM31CR71E475KA88L
3
2
C3, C4
1µF 100V X7R
ceramic chip capacitor
SMD 1210
Murata
GRM32CR72A105KA88L
4
1
D1
100V 1A Schottky rectifier
SMA
Diodes Inc
B1100-13-F
5
2
J1, J2
2 position 5.08mm pitch
vertical header
Thru-hole
Molex
10-08-5021
6
1
J3
3 position 2.54mm pitch
vertical header
Thru-hole
Molex
22-03-2031
7
1
L1
330µH 0.39A 0.45A sat inductor
SMT
Wurth
Elektronik
744 777 233
8
1
R1
0R68 1/4W 1% chip resistor
SMD 1206
-
-
9
1
R2
1K0 1/8W 1% chip resistor
SMD 0805
-
-
10
1
R4
52K3 1/8W 1% chip resistor
SMD 0805
-
-
11
1
U1
HV9967B Universal LED Driver
MSOP-8
Supertex
HV9967BMG-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)
Supertex inc.
©2013 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited.
Doc.# DSDB-HV9967BDB1
B101613
6
1235 Bordeaux Drive, Sunnyvale, CA 94089
Tel: 408-222-8888
www.supertex.com