HV9910BDB3 Supertex, HV9910BDB3 Datasheet - Page 4

• Manufacturer Part Number: HV9910BDB3
• Description: LED Lighting Development Kits LO VOLT HI BRIGHT LED DRIVER DEMOBOARD
• Manufacturer: Supertex

Frequently Asked Questions
6. Why are the LED current rise and fall times during PWM dimming different when the load changes from
Typical Results
Constant Frequency Mode:
The HV9910BDB3 is designed to be operated in the constant frequency mode when the load is a single LED. In this
mode, the line regulation of the LED current is less than 2% and full-load efficiency greater than 80%.
The LED current rise time is directly proportional to V
input voltage and V
time will be smaller.
one LED to two LEDs?
90
85
80
75
88
86
84
82
Fig. 1. Efficiency vs. Input Voltage Plot
Fig. 3. Efficiency vs. Load Voltage Plot
2
Efficiency vs. Input Voltage (@ V
8
Efficiency vs. Load Voltage
12
OUT
is the output voltage). Since V
16
(@ V
Input Voltage (V)
3
Load Voltage (V)
IN
= 12V)
●
20
1235 Bordeaux Drive, Sunnyvale, CA 94089
24
4
(cont.)
O
28
= 4V)
32
5
OUT
IN
- V
is higher with two LEDs, the rise time will be larger and the fall
4
OUT
and the fall time is proportional to V
Fig. 4. Load Regulation of LED Current Plot
-1
-2
Fig. 2. Line Regulation of LED Current Plot
2
1
0
3
2
1
0
8
2
●
Load Regulation (@ V
Tel: [phone]
Line Regulation (@ V
12
16
Input Voltage (V)
3
Load Voltage (V)
20
●
www.supertex.com
IN
24
O
4
= 12V)
= 4V)
HV9910BDB3
OUT
28
(where V
32
5
IN
is the