LT1947 LINER [Linear Technology], LT1947 Datasheet - Page 6

• Manufacturer Part Number: LT1947
• Description: Adjustable Output TFT-LCD Triple Switching Regulator
• Manufacturer: LINER [Linear Technology]

OPERATIO
LT1947
TYPICAL APPLICATIO S
V
6
SS
CERAMIC
33nF
33.2k
C
R
SS
SS
2.2 F
C1: TAIYO YUDEN LMK316BJ225MD
C2: TAIYO YUDEN LMK325BJ335MD 2
C3: AVX 0.22 F 25V X7R
C4, C6: TAIYO YUDEN LMK107BJ684MA
V
IN
Figure 3. R
V
C1
OFF
U
SS
L2
4.7 H
D2
C3
220nF
and C
SS
R3
182k
R4
10k
SHUTDOWN
at SHDN Pin Provide Soft-Start
CERAMIC
SW2
V
FB2
O2
SHDN C
10nF
3.3V
V
2.2 F
C1: TAIYO YUDEN LMK316BJ225MD 2.2 F X7R
C2: TAIYO YUDEN LMK325BJ335MD 3.3 F X5R
C3, C6: AVX 0.22 F CERAMIC X7R
C4: TAIYO YUDEN EMK212BJ684MD
V
IN
C5
U
IN
C1
D1: MBRM120LT3
D2: CMDSH-3
D3, D4: BAT54S DUAL DIODE
L1: SUMIDA CLQ4D103R3
L2: TAIYO YUDEN LB2012B4R7M
LT1947
3.3 H
L1
T
TFT-LCD Bias Generator: 10V, 24V, – 6V Output
D3
SW1
GND
V
FB1
ON
D1
L2
4.7 H
C6
0.68 F
D2
C3
220nF
D4
R1
53.6k
R2
10k
R3
182k
R4
10k
1947 F03
SW2
V
FB2
C4
0.68 F
CERAMIC
C2
3.3 F
CERAMIC
O2
SHDN C
10nF
2
V
AV
8V
200mA
V
–8V
10mA
V
24V
10mA
IN
C5
OFF
ON
DD
LT1947
3.3 H
L1
T
D3
D1: MBRM120
D2: CMDSH-3
L1: SUMIDA CLQ4DI03R3
L2: TAIYO YUDEN LB2012B-4R7M
SW1
GND
BAT54S
V
FB1
ON
20V/DIV
10V/DIV
10V/DIV
D1
5V/DIV
C6
220nF
AV
V
D4
V
V
OFF
ON
SS
DD
R1
69.8k
R2
10k
1947 TA04
C4
0.68 F
C2
3.3 F
CERAMIC
2
Figure 4. Start-Up Waveforms
with Soft-Start Circuit Added
AV
10V
150mA
V
–6V
10mA
V
24V
10mA
OFF
ON
DD
5ms/DIV
1947 F04.tif
1947f