
Six-String WLED Driver with Integrated
Step-Up Converter
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1. V IN = 12V, C COMP = 0.51nF, C COUT = 4.7μF, R COMP = 82.5k?, R ISET = 180k?, R FSLCT = 100k?, L = 10μH,
T A = 0°C to +85°C , unless otherwise noted. Typical values are at T A = +25°C.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
FPO OUTPUT
FPO Off-Leakage Current
FPO On Output-Voltage
Low
Fault inactive, T A = +25 N C
I SINK = 1mA, fault active
100
0.4
nA
V
INPUT LEAKAGE
PWM Leakage Current
OVP Leakage Current
T A = +25 N C, V PWM = 0V, V PWM = 5V
T A = +25 N C, V OVP = 0V, V OVP = 5V
-1
-0.1
+1
+0.1
F A
F A
LED CURRENT
R ISET = 120k I
29.1
30
30.9
Full-Scale FB_ Output
Current
R ISET Range
Current Regulation
Between Strings
Minimum FB_ Regulation
Voltage
R ISET = 180k I
R ISET = 360k I
V ISET < 0.7V
Operating range
Accuracy = 3%
10mA < I FB _< 30mA
I FB _ = 30mA
I FB _ = 20mA
I FB _ = 10mA
19.6
9.7
0.2
100
120
-2.0
400
20
10
0.3
555
460
350
20.4
10.3
0.4
400
360
+2.0
770
670
630
mA
k I
%
mV
FB_ On-Resistance
FB_ Bias Current
FB_ Minimum On-Time
V FB _ = 50mV (includes 10 I sense resistor)
V FB _ = 40V, T A = +25 N C
400
17.5
0.1
580
28.4
1
700
I
F A
ns
FAULT PROTECTION
OVP Threshold Voltage
FB_ Overvoltage
Threshold
Rising edge, typical hysteresis = 90mV
1.23
7
1.25
8
1.27
9
V
V
FB_ Enable Threshold
Voltage
1.2
V
FB_ Open Threshold
Voltage
FB_ Check LED Source
Current
130
0.4
280
1.3
mV
mA
FB_ Check LED Time
Thermal-Shutdown
Threshold
Overcurrent Fault Timer
(Note 1)
Latch-off timer
0.7
1.0
+150
128
1.3
ms
N C
F s
PWM CONTROL
PWM Input On-Time
400
ns
PWM Input Frequency
Range
0.1
25
kHz
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