Datasheet

EN
ip
i
h
VIN
TPS54620
R 1
R 2
EN
ip
i
h
PVIN
TPS54620
R 1
R 2
EN
ip
i
h
VIN
TPS54620
R 1
R 2
PVIN
1
æ ö
-
ç ÷
è ø
æ ö
- +
ç ÷
è ø
ENFALLING
START STOP
ENRISING
ENFALLING
p h
ENRISING
V
V V
V
R1 =
V
I I
V
( )
´
- + +
ENFALLING
STOP ENFALLING p h
R1 V
R2 =
V V R1 I I
TPS54620
SLVS949C – MAY 2009– REVISED MAY 2011 www.ti.com
Figure 17. Adjustable VIN Under Voltage Lock Out
Figure 18. Adjustable PVIN Under Voltage Lock Out, VIN ≥ 4.5V
Figure 19. Adjustable VIN and PVIN Under Voltage Lock Out
(2)
(3)
Where I
h
= 3.4 μA, I
p
= 1.15 μA, V
ENRISING
= 1.21 V, V
ENFALLING
= 1.17 V
Adjustable Switching Frequency and Synchronization (RT/CLK)
The RT/CLK pin can be used to set the switching frequency of the device in two modes.
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