Datasheet

TPS54680
SLVS429B − OCTOBER 2002 − REVISED OCTOBER 2005
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13
Figure 21 shows the schematic diagram for a power
supply tracking design using a TPS2034 high side power
switch and a TPS54680 device. The TPS2034 power
switch ensures the I/O voltage is not applied to the load
before U1 has enough bias voltage to operate and
generate the core voltage.
R3
Distribution Switch
VOUT_I/O
U1
RT
ENA
TRACKIN
VBIAS
VIN
VIN
VIN
VIN
VIN
PGND
PGND
PGND
PGND
PGND
PwrPad
AGND
VSENSE
COMP
PWRGD
BOOT
PH
PH
PH
PH
PH
PH
PH
PH
PH
28
27
26
25
24
23
22
21
20
19
18
17
16
15 14
13
12
11
10
9
8
7
6
5
4
3
2
1
10 kΩ
R1
10 kΩ
R4
10 kΩ
R6
9.76 kΩ
VIN
C6
10 µF
C7
10 µF
C2
1 µF
C5
0.047 µF
L1
0.65 µH
R9
2.2 Ω
C11
3300 pF
C1
470 pF
C4
12 pF
R5
10 kΩ
C8
22 µF
C9
22 µF
C10
22 µF
R7
301 Ω
C3
470 pF
R8
9.76 kΩ
R2
71.5 kΩ
Analog and Power Grounds are Tied at
the Power Pad Under the Package of IC
VOUT_CORE
TPS2034
Figure 21. 3.3-V Small Size, High Frequency Design