LT1182 LINER [Linear Technology], LT1182 Datasheet - Page 4

• Manufacturer Part Number: LT1182
• Description: CCFL/LCD Contrast Switching Regulators
• Manufacturer: LINER [Linear Technology]

LT1182/LT1183/LT1184/LT1184F
T
(LT1182/LT1183) LCD V
(LT1183/LT1184/LT1184F) REF = Open, unless otherwise specified.
SYMBOL
REF1
g
I
V
The
temperature range.
Note 1: T
dissipation P
LT1182CS/LT1183CS/LT1184CS/LT1184FCS: T
4
ELECTRICAL CHARACTERISTICS
LIM2
A
m
SAT2
I
SW2
I
= 25 C, V
Q
denotes specifications which apply over the specified operating
J
is calculated from the ambient temperature T
V
V
REF1 Voltage Line Regulation
FBP/FB Input Bias Current
LCD FBN/FB Offset Voltage
Offset Voltage Line Regulation
FBN/FB Input Bias Current
FBP/FB to LCD V
FBN/FB to LCD V
LCD Error Amplifier Source Current
LCD Error Amplifier Sink Current
LCD V
LCD V
LCD V
LCD Switch Current Limit
LCD Switch On-Resistance
Supply Current Increase During
LCD Switch On-Time
Switch Minimum On-Time
PARAMETER
LCD FBP/FB Reference Voltage
D
REF
REF
IN
according to the following formula:
= 5V, BAT = Royer = Bulb = 12V, I
– I
– I
C
C
C
CCFL
CCFL
Low Clamp Voltage
High Clamp Voltage
Switching Threshold
Summing Voltage
Summing Voltage
C
= 0.5V, LCD V
C
C
Transconductance
Transconductance
SW
J
= T
= Open, (LT1182) FBN = FBP = GND, (LT1183) FB = GND,
A
CONDITIONS
Measured on LT1183
Measured on LT1184/LT1184F
LT1182: Measured at FBP Pin, FBN = 1V, LCD V
LT1183: Measured at FB Pin, LCD V
3V V
LT1182: FBP = REF1, FBN = 1V, LCD V
LT1183: FB = REF1, LCD V
LT1182: Measured at FBN Pin, FBP = 0V, LCD V
LT1183: Measured at FB Pin, LCD V
3V V
LT1182: FBN = Offset Voltage, FBP = 0V, LCD V
LT1183: FB = Offset Voltage, LCD V
LT1182: I
LT1183: I
LT1182: I
LT1183: I
LT1182: FBP = FBN = 1V or 0.25V,
LT1183: FB = 1V or 0.25V
LT1182: FBP = FBN = 1.5V or – 0.25V,
LT1183: FB = 1.5V or – 0.25V
LT1182: FBP = FBN = 1.5V, LT1183: FB = 1.5V
LT1182: FBP = FBN = 1V, LT1183: FB = 1V
LT1182: FBP = FBN = 1V, LT1183: FB = 1V, V
Duty Cycle = 50%
Duty Cycle = 75% (Note 3)
LCD I
LCD I
Measured at CCFL V
+ (P
CCFL
A
and power
D
SW
SW
IN
IN
= SHUTDOWN = CCFL V
100 C/W)
= 0.5A
= 0.5A
30V, LCD V
30V, LCD V
VC
VC
VC
VC
= 25 A, FBN = 1V
= 25 A
= 25 A
= 25 A, FBP = GND
SW
C
C
and LCD V
= 0.8V
= 0.8V
Note 2: Does not include switch leakage.
Note 3: For duty cycles (DC) between 50% and 75%, minimum
guaranteed switch current is given by I
regulator and I
internal slope compensation circuitry.
C
= 0.8V
SW
SW
C
C
C
= 0.8V
= 0.8V
= 0.8V
= Open, DIO = GND, CCFL V
C
= 0.8V
LIM
= 0.7(1.393 – DC ) for the LCD contrast regulator due to
SW
C
C
C
DC = 0%
= 0.8V
= 0.8V
= 0.8V
LIM
0.740
0.760
0.725
0.705
1.224
1.214
0.625
0.400
– 3.0
MIN
– 20
– 27
650
500
550
400
1.7
0.6
50
35
= 1.4(1.393 – DC) for the CCFL
C
= 0.5V,
0.795
0.795
0.775
0.775
1.244
1.244
– 1.0
0.01
0.35
0.01
0.01
0.95
1.00
0.85
0.45
TYP
– 12
– 12
900
900
800
800
100
100
2.0
1.0
20
0.830
0.865
0.810
0.845
1.264
1.274
1150
1300
1050
1200
MAX
0.03
1.65
175
175
1.0
0.2
0.3
2.4
1.3
1.5
1.3
– 4
– 1
30
UNITS
mhos
mhos
mhos
mhos
mA/A
%/V
%/V
mV
mV
V
V
V
V
V
V
A
A
A
A
V
V
V
A
A
s