Datasheet

MAX8795A
TFT-LCD DC-DC Converter with
Operational Amplifiers
______________________________________________________________________________________ 15
Typical Operating Circuit
The MAX8795A typical operating circuit (Figure 1) is a
complete power-supply system for TFT LCDs. The circuit
generates a +14V source-driver supply and +25V and
-10V gate-driver supplies. The input voltage range for the
IC is from +2.5V to +5.5V. The listed load currents in
Figure 1 are available from a +4.5V to +5.5V supply.
Table 1 lists some recommended components, and Table
2 lists the contact information of component suppliers.
C3
0.1µF
C4
0.1µF
C14
68pF
C11
0.1µF
LX
D1
L1
3.0µH
LX
C2
22µF
D2
V
MAIN
14V/500mA
R1
137kΩ
1%
R2
13.3kΩ
1%
R3
6.8kΩ
R6
1kΩ
R19
100kΩ
R20
100kΩ
R17
100kΩ
R18
100kΩ
R15
100kΩ
R16
100kΩ
R13
100kΩ
R14
100kΩ
R11
100kΩ
R12
100kΩ
R4
191kΩ
1%
R5
10.0kΩ
1%
Q1
C5
0.47µF
V
GON
25V/20mA
C6
0.1µF
LX
V
IN
4.5V TO 5.5V
D3
Q2
C1
22µF
C12
220µF
C13
0.1µF
R10
10Ω
180kΩ
R9
6.8kΩ
C10
0.1µF
R7
324kΩ
1%
R8
31.6kΩ
1%
C9
0.22µF
C8
0.22µF
V
GOFF
-10V/50mA
C7
0.033µF
TO VCOM
BACKPLANE
IN
COMP
DRVN
FBN
REF
FB
AGND
PGND
DRVP
FBP
SRC
COM
LX
DEL
NEG1
NEG2
OUT2
OUT3
NEG4
OUT4
NEG5
OUT5
OUT1
DRN
CTL
SUP
BGND
POS1
POS2
POS3
POS4
POS5
MAX8795A
EP
Figure 1. Typical Operating Circuit
DESIGNATION DESCRIPTION
C1
22µF, 6.3V X5R ceramic capacitor (1210)
TDK C3225X5R0J227M
C2
22µF, 16V X5R ceramic capacitor (1812)
TDK C4532X5X1C226M
D1
3A, 30V Schottky diode (M-flat)
Toshiba CMS02
D2, D3
200mA, 100V, dual ultra-fast diodes (SOT23)
Fairchild MMBD4148SE
DESIGNATION DESCRIPTION
L1
3.0µH, 3A inductor
Sumida CDRH6D28-3R0
Q1
200mA, 40V pnp bipolar transistor (SOT23)
Fairchild MMBT3906
Q2
200mA, 40V npn bipolar transistor (SOT23)
Fairchild MMBT3904
Table 1. Component List