Datasheet

V
OUT
I
OUT
Hard Short
Detection
A moderate short
occurs on Vout
V is tied directly to V
ON IN
Current increases
through switch
proportional to V
OUT
t
PWRON
V /2
IN
V /2
OUT
V
IN
0V
V
ON
0V
Over current
Current is
limited
No current
Switch is off
ON
OFF
Moderate Over Current
Detection
t
MODOC
Over Temperature
Detection
8mS
ONOFF
8mS
0.125 ms
OFFOFFOFFOFFOFF OFF
OFF
ONONONONON ONON ON
ONOFF
t
BLANK
t
BLANK
t
RSTART
t
RSTART
ON
Inrush current window
Inrush current window
t
OVRTMP
t
TIMEOUT
t
HARDSHORT
SWITCH
OPEN
SWITCH
CLOSE
SWITCH
OPEN
Load Switch Status
TPS22946
www.ti.com SLVS984A –SEPTEMBER 2009–REVISED FEBRUARY 2010
Moderate Over-Current Detection
The moderate over-current detection circuit is active every 64 ms for a period of 0.5 ms. A moderate over-current
condition is triggered when the output current of the switch exceeds the current limit value and is not yet into
hard short condition. The switch then goes into current-limiting mode.
NOTE: The over current does n’t cause the temperature to go above 140°C here.
Figure 28. Moderate Over-Current Detection
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