|
The MAX1564 triple, current-limited USB switch comes
in a space-saving, 16-pin, 4mm x 4mm thin QFN package.
Each channel meets all IEC specifications for USB
ports. The device is capable of supplying up to 1.2A
from each output. The MAX1564 has multiple protection
features, including thermal shutdown to limit junction
temperature in case of a prolonged short or overload
condition. Reverse-current protection circuitry blocks
current flow from output to input regardless of the
switch state. The IC has accurate, user-programmable
current-limiting circuitry to protect the input supply
against overload.
Each output of the MAX1564 has short-circuit protection
that latches off the switch when the output is shorted
for more than 20ms, thereby saving system power.
Auto-restart then tests the shorted output with a 25mA
current to determine when the short is removed, then
automatically restarts the output. Independent opendrain
fault signals notify the microprocessor that the
internal current limit has been reached. A 20ms faultblanking
feature allows momentary faults to be ignored,
such as those caused when hot-swapping into a
capacitive load. This feature helps avoid issuing false
alarms to the host system. Blanking also suppresses
errant fault signals when the device is powering up.
|