Electronic Resettable Fuse
General Description
The AAT4680 electronic resettable fuse is a mem-
ber of AnalogicTech’s Application Specific Power
MOSFET™ (ASPM™) product family. It is a 1A
current limited P-channel MOSFET power device
that remains fully enhanced as long as the input
power supply is above an under-voltage lockout
threshold and the load is below the current limit
setting. If the load increases above the current
limit setting, as is the case during a short circuit,
the MOSFET effectively becomes a constant cur-
rent source equal to the current limit. If the current
limit condition persists long enough to heat the
MOSFET to an extreme temperature, the device
will thermal cycle off and on until the current limit
condition is removed. An open drain FAULT flag
signals an over-current or over-temperature condi-
tion. Quiescent current is typically a low 10µA.
The AAT4680 is available in a Pb-free, 5-pin
SOT23 package and is specified over the -40°C to
+85°C temperature range.
AAT4680
Features
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SmartSwitch
™
500mA Steady State Load Current
600mA Minimum Current Limit Trip Point
Low Quiescent Current: Typically 10µA
Over-Temperature Protection
Fast Transient Tesponse:
— <1µs Response to Short Circuit
400mΩ Typical R
DS(ON)
Under-Voltage Lockout
FAULT Flag with 3ms Blanking
5-Pin SOT23 Package
Temperature Range: -40°C to +85°C
Applications
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Cell Phone Ports
Desktop PCs
Peripheral Ports
USB Ports
Typical Application
INPUT
5
IN
OUT
1
AAT4680
FAULT
C
IN
1μF
GND
2
3
OUT
FAULT
C
OUT
1μF
GND
GND
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