
LX1745
P
RODUCTION
D
ATASHEET
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
W
M
.
C
Triple Output Boost – LED Driver / LCD Bias
I N T E G R A T E D P R O D U C T S
Copyright
2000
Rev. 1.1a, 2004-02-06
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the operating ambient temperature 0
°
C
≤
T
A
≤
70
°
C except where
otherwise noted and the following test conditions:
V
IN
= 3V,
LSHDN
= V
IN
,
1
SHDN
= V
IN
,
2
SHDN
= V
IN
LX1745
Typ
Parameter
Symbol
Test Conditions
Min
Max
Units
`
LED DRIVER
V
BRT
= 100mV
V
BRT
= 20mV
V
LFB
= 100mV
BRT = 100mv
85
5
-100
0
100
20
115
35
100
VIN
60
LFB Threshold Voltage
V
LFB
mV
LFB Input Bias Current
BRT Input Voltage Range
BRT Input Bias Current
LED Driver Shutdown Input
Bias Current
Current Sense Bias Current
I
LFB
V
BRT
I
BRT
nA
V
nA
I
1
SHDN
0.0V
≤
R
CS
= 0k
R
CS
= 2k
V
IN
= 5V, V
DRV
= 3V
V
CC
= 5V
V
FB
= 1V
V
FB
= 1V
1
SHDN
≤
VIN
-100
100
nA
I
CS
4
μ
A
170
210
100
12
300
1.21
1.21
Switch Peak Current
I
PK
mA
DRV Sink/Source Current
DRV On-Resistance
Maximum Switch On-Time
Minimum Switch Off-Time
OVP Threshold Voltage
Reference Voltage
LCD BIAS
Output Voltage Range
FBx Threshold Voltage
FBx Input Current
LCD Bias Shutdown Input Bias
Current
Peak Inductor Current
Internal NFET On-resistance
Switch Pin Leakage Current
Switch On-Time
Switch Off-Time
ADJx Input Voltage Range
ADJx Input Bias Current
ENTIRE REGULATOR
Operating Voltage
Minimum Start-up Voltage
Start-up Voltage Temperature
Coefficient
Shutdown High Input Voltage
Shutdown Low Input Voltage
85
200
1.15
1.186
mA
μ
S
nS
R
DRV(ON)
t
ON
t
OFF
V
OVP
V
REF
15
∞
410
1.26
1.234
V
`
V
OUT
V
FB
I
FB
V
FB
= 1.4V
25
V
V
nA
1.166
1.190 1.214
200
I
SHDNx
SHDNx
= GND
T
A
= +25
°
C
I
SW
= 10mA, T
A
= +25
°
C, V
IN
= 5V
V
SW
= 25V
V
FB
= 1V
V
FB
= 1V
100
nA
I
LIM
330
1.1
0.3
mA
μ
A
μ
s
ns
V
μ
A
R
DS(ON)
I
LEAK
t
ON
t
OFF
V
ADJx
I
ADJx
1.0
∞
400
1.5
1.0
150
0.9
`
V
IN
Recommended Operating Range
T
A
= +25
°
C
1.6
6.0
1.6
V
V
κ
-2
mV/
°
C
V
SHDNx
V
SHDNx
V
IN
= 2V
V
IN
= 2V
V
FBx
= 1.4V, V
LFB
> V
BRT
– 0.1V
V
FBx
= 1.4V, V
LFB
> V
BRT
– 0.1V, V
LSHDN
<
0.4V
V
FBx
= 1.4V, V
LFB
> V
BRT
– 0.1V, V
0.4V
V
FBx
= 1.4V, V
LFB
> V
BRT
– 0.1V, V
0.4V
V
1
0.4V
1.6
V
V
0.4
320
200
0.35
1
1
SHDN
<
140
220
2
SHDN
<
80
120
Quiescent Current
I
Q
SHDN
< 0.4V, V
2
SHDN
< 0.4V, V
LSHDN
<
0.35
1
μ
A
E
L
E
C
T
R
I
C
A
L
S