BD8108FM Datasheet, PDF (1/16 Pages) Rohm – White LED driver IC (under development) HSOP-M28 package

TECHNICAL NOTE
For LCD panel backlight
White LED driver ICʢunder developmentʣ
BD8108FM
rev. 0.14
● Outline
BD8108FM is a white LED driver of high-withstand-voltage (36V).
Step-up DC/DC converter and constant current output 4ch are built-in in 1chip.
The brightness can be controlled by either PWM or VDAC.
● Features
1) Input voltage range
4.5ʙ30V
2) Built-in Step-up DC/DC controller
3) Built-in current driver 4ch (150mA max.) for LED drive
4) Compatible with PWM light-modulating
0.38ʙ99.5%
5) Built-in protective functions (UVLO, OVP, TSD, OCP)
6) Built-in abnormal-status-detecting function (open/short)
7) HSOP-M28 package
● Application
Car navigation backlight and small & medium-sized LCD panel etc.
● Absolute maximum ratings (Ta=25ˆ)
Item
Symbol
Rating
Unit
Power supply voltage (Pin : 1)
VCC
36
V
Load switch output voltage (Pin : 2)
VLOADSW
36
V
LED output voltage(Pin : 12,14,15,17)
VLED
36
V
FAIL output voltage (Pin : 3,20)
VOL
7
V
Input voltage (Pin : 5,6,10,11,24)
VIN
-0.3ʙ7 < VCC
V
VDAC input voltage (Pin : 8)
Allowable loss
VDAC
-0.3ʙ7 < VCC
V
Pd
2.20 ^˞1
W
Junction temperature
Tjmax
150
ˆ

Operating temperature range
Topr
-40ʙ+95
ˆ

Storage temperature range
Tstg

-55ʙ+150
ˆ

LED maximum output current (Pin :
ILED



150
^˞
˞
mA
12,14,15,17)
˞1 It is mounted on a glass epoxy board of 70mm×70mm×1.6mm. And the allowable loss is reduced at a rate of 17.6mw/ˆ
at the time of over 25ˆ

˞2 Dispersion between columns of LED maximum output current and V_F is correlated. Please refer to data on a separate
sheet.
˞3 Amount of the current per 1ch.
● Operating condition (Ta=25ˆ)
Item
Symbol
Target value
Unit
Power supply voltage (Pin : 1)
VCC
4.5ʙ30
V
Oscillating frequency range
FOSC
50ʙ550
kHz
External synchronization frequency
FSYNC
foscʙ550
kHz
range ^˞
˞(Pin : 6)
External synchronization pulse duty
FSDUTY
40ʙ60
%
range (Pin : 6)
˞4 Please connect SYNC to GND when external synchronization frequency is not used.
˞5 Do not do such things as switching over to internal oscillating frequency while external synchronization frequency is
used.
2007.Jan.
ROHM Limited Corporation