LT1184F_15 Datasheet, PDF (13/24 Pages) Linear Technology – CCFL/LCD Contrast Switching Regulators

BLOCK DIAGRAM
LT1182/LT1183/LT1184/LT1184F
LT1182/LT1183 CCFL/LCD Contrast Regulator Top Level Block Diagram
V_IN
BAT ROYER
12
14
13
SHUTDOWN 6
SHUTDOWN
LCD
V_SW
9
Q2
DRIVE 2
LOGIC 2
ANTI-
SAT2
R2
0.25Ω
+
I_LIM
AMP2
–
GAIN = 4.4
COMP2
0µA TO
100µA
LCD
+––+
+
V2
1.24V
– ^–12mV
+
CCFL
–
V1
0.45V
2.4V
REGULATOR
UNDER-
VOLTAGE
LOCKOUT
200kHz
OSC
Q5
1×
Q3
2×
Q4 Q7
5× 9×
THERMAL
SHUTDOWN
R4
0.1Ω
LOGIC 1
–+
D2
g_m
6V
R3
1k
Q6
2×
Q11
COMP1
Q8
1×
Q9
Q10
3×
2×
D1
87
LCD LCD
PGND V_C
11 10
2
FBP FBN I_CCFL
5
3
AGND
DIO
LT1183: FBP AND FBN ARE TIED TOGETHER TO CREATE FB
AT PIN 10. THE REFERENCE IS BROUGHT OUT TO PIN 11.
15
BULB
4
CCFL
V_C
CCFL
V_SW
16
DRIVE 1
Q1
ANTI-
SAT1
+
I_LIM
AMP1
–
GAIN = 4.4
R1
0.125Ω
1
CCFL
PGND
1182 BD01
13