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SLVS456C − OCTOBER 2003 − REVISED OCTOBER 2004
U1
C1
TPS54350PWP
0.1 µF
5 V
L1
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
VIN
22 µH
BOOT
GND
1
2
R2
PH
VIN
+
100 kΩ
C3
10 µF
C2
8
7
4
6 5
UVLO
PH
LSG
220 µF
D-Case Alum
C7
10 µF
Q1
PWRGD
RT
R3
43.2 kΩ
VBIAS
+
SYNC
ENA
PGND
AGND
C4
220 µF
D-Case Alum
C5
1 µF
C6
COMP
VSENSE
22 µF
(1)
PWRPAD
17
3
2 1
VOUT
–5 V @ 1.5 A
C9
2200 pF
(1)
R9
130 kΩ
R8
100 kΩ
C10
470 pF
R4
3.09 kΩ
C8
470 pF
C4: Panasonic EEVFK1A221XP
L1: Coilcraft DO3340P-223
Q1: International Rectifier IRF7402
R1
21.5 kΩ
(1)
Do not connect to system ground plane.
(1)
Figure 27. Inverting Power Supply, 5 V to −5 V at 1.5 A
In Figure 27 the TPS54350 is configured as an inverting
supply. The −5-V output is at the pins which would normally
be connected to ground. The output junction of the LC
output filter, which is normally the output in a buck
converter, is tied to ground. An additional 10-µF capacitor,
C7, is required from the output to VIN.
U1
C1
TPS54350PWP
0.1 µF
L1
1
2
3
4
5
6
7
8
16
15
14
13
+12 V
10 µH
VIN
BOOT
PH
VOUT 5 V @ 3 A
C2
10 µF
16 V
VIN
UVLO
PH
LSG
PWRGD
RT
12
11
10
9
VBIAS
+
D1
C3
SYNC
ENA
PGND
AGND
220 µF
C4
R1
80.6 kW
C5
1 µF
6.3 V
10 µF
6.3 V
COMP
VSENSE
PWRPAD
17
C7
0.01 µF
R2
5.90 kΩ
R3
4.64 kΩ
C8
4700 pF
R4
7.50 kΩ
C9
10 pF
R5
1 kΩ
D1: On Semiconductor MBRS340T3
C3: Panasonic EEVFK0J221P
L1: Coilcraft DO3316P-103
Figure 28. 12-V to 5-V Using Aluminum Electrolytic for LCD TV
Figure 28 is an example of a 12-V to 5-V converter using economical output filter components.
21
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