AAT4644
4-Channel Current Limited Load Switch
General Description
The AAT4644 is a four-channel resettable fuse. It
utilizes independent current-limited and thermally
protected P-channel MOSFETs to protect against
short circuits. Each switch's current limit is factory
programmed at 1A. Additional protection is provid-
ed with undervoltage lockout; the switches are
turned off when the input voltage drops below a
preset level. The quiescent supply current is typi-
cally 20µA. The AAT4644 is a flexible solution,
allowing system designers to gang outputs togeth-
er for lower R
DS(ON)
and higher current limit.
The AAT4644 is available in 8 pin TSSOP or SOP
packages, specified over -40 to 85°C.
Features
•
•
•
•
•
•
•
•
SmartSwitch
™
500mA per channel steady state
4 X 1A current limit trip point
Over-temp protection
Fast transient response:
• 1µs (typ) response to short circuit
100mΩ typical R
DS(ON)
Undervoltage Lockout
Temp range -40 to 85°C
8 pin TSSOP or SOP packages
Preliminary Information
Applications
•
•
•
USB ports
Peripheral ports
Desktop PCs
Typical Application
INPUT
3.3V - 5V
2,7
IN
OUT1
1
3
8
6
OUTPUT1
OUTPUT2
OUTPUT3
OUTPUT4
AAT4644
GND
4
OUT2
OUT3
OUT4
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