BD9483F Datasheet, PDF (12/32 Pages) Rohm – White LED Driver for large LCD Panels (DCDC Converter type)

BD9483F,FV
Datasheet
●3.2 The detection condition list of the protection (TYP. Condition)
Protection
Detection
Detect condition
pin
pin condition
PWM
SS
FBMAX
FB
FB > 4.0V
H(8clk) SS>4.0V
Release
condition
FB < 4.0V
Timer
operation
CP charge
Protection type
Latch off
LED OCP
ISENSE
ISENSE > 3.0V
-
-
ISENSE < 3.0V
4clk
Latch off
UVLO
UVLO
UVLO<2.8V
-
-
UVLO>3.0V
NO
Auto recovery
REG90UVLO
REG90
REG90<6.0V
-
-
REG90>6.5V
NO
Auto recovery
VCC UVLO
VCC
VCC<6.7V
-
-
VCC>7.0V
NO
Auto recovery
OVP
OVP
OVP>3.0V
-
-
OVP<2.9V
4clk
Latch off
OCP
CS
CS>0.4V
-
-
-
NO
Pulse by Pulse
To reset the latch type protection, please input of STB logic to ‘L’ once. Otherwise the detection of VCCUVLO, REG90UVLO is
required.
In the latch off mode, both channels will be stopped. (GATE1=GATE2=L, DIMOUT1=DIMOUT2=L)
The clock number of timer operation is the correspond to the boost pulse clock.
●3.3 The behavior list of the protection
Protect Function
FBMAX
DC/DC Gate
output
Stops after latch
LED OCP
Stops immediately
STB
Stops immediately
UVLO
Stops immediately
REG90UVLO
Stops immediately
VCC UVLO
Stops immediately
OVP
Stops immediately
OCP
Stops immediately
Please refer to the timing chart for the detail.
The operation of the protection
Dimming transistor
(DIMOUT) logic
SS pin
L after latch
discharge after latch
H immediately, L after latch
discharge after latch
L after REG90UVLO detects discharge immediately
immediately L
discharge immediately
immediately L
discharge immediately
immediately L
discharge immediately
immediately L
discharge after latch
Normal operation
Not discharge
FAILB pin
(NORMAL=open)
L after latch
L after latch
OPEN
Low
OPEN
Low
L after latch
OPEN
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TSZ22111・15・001
12/29
TSZ02201-0F1F0C100100-1-2
28.Nov.2013 Rev.003