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Rainbow Electronics MAX1558H User Manual

Page 11

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For a 5V input and 1V output, the maximum possible
power dissipation per switch is:

P = 0.5 x (1.5A) x (5V - 1V) = 3W

Since the package power dissipation is limited to
1952mW, the MAX1558/MAX1558H die temperature
exceeds the thermal-shutdown threshold and the
switch turns off. After the die temperature cools by
10

°C, the switch turns on again. If the fault-overload

condition continues, the switch cycles on and off with a
duty cycle and period that is a function of the ambient
temperature and PC board layout.

A short across the output for more than 20ms places
the part in autoreset mode. With V

IN_

= 5V and an

autoreset test current of 30mA, the power dissipation
for a short-circuited output is given by:

P = (30mA) x 5V = 0.15W

MAX1558/MAX1558H

Dual, 3mm x 3mm, 1.2A/Programmable-Current

USB Switches with Autoreset

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11

Chip Information

TRANSISTOR COUNT: 2932

PROCESS: BiCMOS