AAT4611 Datasheet, PDF (9/12 Pages) Advanced Analogic Technologies – Current Limited Load Switch in SOT-23 Package

AAT4611
Current Limited Load Switch in SOT-23 Package
5
4
3
2
1
0
- 0 .0 5
Overload Operation
1Ω load is turned on at time = 0
Output Current
Output Voltage
0
0.05
0.1
0 .15
0 .2
0.25
Tim e ( s )
1
0.75
0.5
0.25
0
0.3
Operation in Current Limit
When a heavy load is applied to the output of the
AAT4611, the load current is limited to the value of
I_LIM determined by R_SET. See the figure "Overload
Operation". Since the load is demanding more cur-
rent than I_LIM, the voltage at the output drops. This
causes the AAT4611 to dissipate a larger than nor-
mal quantity of power, and its die temperature to
increase. When the die temperature exceeds an
over temperature limit, the AAT4611 will shut down
until is has cooled sufficiently, at which point it will
startup again. The AAT4611 will continue to cycle
on and off until the load is removed, power is
removed, or until a logic high level is applied to ON
(pin 4).
Enable Input
In many systems, power planes are controlled by
integrated circuits which run at lower voltages than
the power plane itself. The enable input ON (pin 4)
of the AAT4611 has low and high threshold volt-
ages that accommodate this condition. The thresh-
old voltages are compatible with 5 volt TTL, and 2.5
volt to 5 volt CMOS.
Reverse Voltage
The AAT4611 is designed to control current flowing
from IN to OUT. If a voltage is applied to OUT which
is greater than the voltage on IN, large currents may
flow. This could cause damage to the AAT4611.
4611.2001.8.0.9
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