LT1183_15 Datasheet, PDF (3/24 Pages) Linear Technology – CCFL/LCD Contrast Switching Regulators

LT1182/LT1183/LT1184/LT1184F
ELECTRICAL CHARACTERISTICS
T_A = 25°C, V_IN = 5V, BAT = Royer = Bulb = 12V, I_CCFL = SHUTDOWN = CCFL V_SW = Open, DIO = GND, CCFL V_C = 0.5V,
(LT1182/LT1183) LCD V_C = 0.5V, LCD V_SW = Open, (LT1182) FBN = FBP = GND, (LT1183) FB = GND,
(LT1183/LT1184/LT1184F) REF = Open, unless otherwise specified.
SYMBOL PARAMETER
I_Q
Supply Current
I_SHDN
f
SHUTDOWN Supply Current
SHUTDOWN Input Bias Current
SHUTDOWN Threshold Voltage
Switching Frequency
DC(MAX) Maximum Switch Duty Cycle
CONDITIONS
LT1182/LT1183: 3V ≤ V_IN ≤ 30V
LT1184/LT1184F: 3V ≤ V_IN ≤ 30V
SHUTDOWN = 0V, CCFL V_C = LCD V_C = Open (Note 2)
SHUTDOWN = 0V, CCFL V_C = LCD V_C = Open
Measured at CCFL V_SW and LCD V_SW, I_SW = 50mA,
I_CCFL = 100µA, CCFL V_C = Open, (LT1182) FBN = FBP =
1V, (LT1183) FB = 1V, (LT1182/LT1183) LCD V_C = Open
Measured at CCFL V_SW and LCD V_SW
BV
Switch Breakdown Voltage
Switch Leakage Current
I_CCFL Summing Voltage
Measured at CCFL V_SW and LCD V_SW
V_SW = 12V, Measured at CCFL V_SW and LCD V_SW
V_SW = 30V, Measured at CCFL V_SW and LCD V_SW
3V ≤ V_IN ≤ 30V, Measured on LT1182/LT1183
3V ≤ V_IN ≤ 30V, Measured on LT1184/LT1184F
I_LIM1
V_SAT1
∆I_Q
∆I_SW1
V_REF
∆I_CCFL Summing Voltage for
∆Input Programming Current
CCFL V_C Offset Sink Current
∆CCFL V_C Source Current for
∆I_CCFL Programming Current
CCFL V_C to DIO Current Servo Ratio
CCFL V_C Low Clamp Voltage
CCFL V_C High Clamp Voltage
CCFL V_C Switching Threshold
CCFL High-Side Sense Servo Current
CCFL High-Side Sense Servo Current
Line Regulation
CCFL High-Side Sense Supply Current
Bulb Protect Servo Voltage
Bulb Input Bias Current
CCFL Switch Current Limit
CCFL Switch On-Resistance
Supply Current Increase During
CCFL Switch On-Time
Reference Voltage
I_CCFL = 0µA to 100µA
CCFL V_C = 1.5V, Positive Current Measured into Pin
I_CCFL = 25µA, 50µA, 75µA, 100µA,
CCFL V_C = 1.5V
DIO = 5mA out of Pin, Measure I_VC at CCFL V_C = 1.5V
V_BAT – V_BULB = Bulb Protect Servo Voltage
I_CCFL = 100µA
CCFL V_SW DC = 0%
I_CCFL = 100µA, I_VC = 0µA at CCFL V_C = 1.5V
BAT = 5V to 30V, I_CCFL = 100µA,
I_VC = 0µA at CCFL V_C = 1.5V
Current Measured into BAT and Royer Pins
I_CCFL = 100µA, I_VC = 0µA at CCFL V_C = 1.5V,
Servo Voltage Measured Between BAT and Bulb Pins
I_CCFL = 100µA, I_VC = 0µA at CCFL V_C = 1.5V
Duty Cycle = 50%
Duty Cycle = 75% (Note 3)
CCFL I_SW = 1A
CCFL I_SW = 1A
Measured at REF (Pin 11) on LT1183/LT1184/LT1184F
Reference Output Impedance
Measured at REF (Pin 11) on LT1183
Measured at REF (Pin 11) on LT1184/LT1184F
MIN
q
q
q 0.6
175
TYP MAX UNITS
9
14
mA
6 9.5
mA
35 70
µA
3
6
µA
0.85 1.2
V
200 225
kHz
q 160 200 240
kHz
80
85
%
q 75
85
%
60
70
V
20
µA
40
µA
0.41 0.45 0.49
V
q 0.37 0.45 0.54
V
0.425 0.465 0.505
V
q 0.385 0.465 0.555
V
5
15
mV
–5
q 4.70
5
15
µA
4.95 5.20 µA/µA
q 94
q
q 1.7
q 0.6
q 0.93
99 104 µA/mA
0.1 0.3
V
2.1 2.4
V
0.95 1.3
V
1.00 1.07
A
0.1 0.16 %/V
q 50 100 150
µA
q 6.5 7.0 7.5
V
5
9
µA
q 1.25 1.9 3.0
A
q 0.9 1.6 2.6
A
q
0.6 1.0
Ω
20 30 mA/A
1.224 1.244 1.264
V
q 1.214 1.244 1.274
V
q 20
45 70
Ω
q5
15 30
Ω
3