BD9285F ROHM [Rohm], BD9285F Datasheet - Page 21

• Manufacturer Part Number: BD9285F
• Description: Boost 1channel white LED driver For large LCDs
• Manufacturer: ROHM [Rohm]

www.rohm.com
© 2012 ROHM Co., Ltd. All rights reserved.
TSZ22111・15・001
BD9285F
●3.4.7. how to set the interval until latch off
BD9285 built in the counter by latch off time, that is performed by counting the oscillation clock which is set by the RT pin.
Since the common oscillation circuit is used for counting, the interval until latch off is corresponding to the 4096 clock,
which the GATE pulse output continuously. Please refer the time chart of the operation from the detect abnormality to the
latch off in the section 3.7.
BD9285 starts the counting up from the detection of each abnormal state, falls to the latch off state when the following
interval has passed.
Only PWM=L input does not reset the timer counter, if the abnormal state continues.
○ ○ ○ ○ latch off time
[setting example]
If the resistor of RT pin is 100k ohm, the timer latch interval is as following.
LATCH
LATCH
Where LATCH
TIME
TIME
R
RT
is the connected resistor of RT pin.
2
4096
12
TIME
1
is the interval until latch off state
R
5 .
1
R
RT
5 .
RT
[
10
[
k
10
10
]
7
]
4096
21/36
4096
1
R
5 .
1
100
RT
5 .
[
k
10
[
k
10
7
]
7
[sec]
]
27
[ 3 .
m
TSZ02201-0F1F0C100030-1-2
sec]
11.Jul.2012 Rev.001
Datasheet