LIFEPAK 20/20e Defibrillator/Monitor
Device Description
Functional Description
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A03 Power Module
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Power Mux
— The power mux switches battery power in and out of VBatt,
depending on power availability and load draw within the device. This circuit
is under supervisory control of the CPU and provides the current voltage
from the A07 Battery and A09 AC Power Supply Module to the CPU. The
circuit automatically switches from ac power to battery power if the voltage
from the ac power supply falls rapidly. Low voltage is detected by the
A09 AC Power Supply Module and broadcast to the other PCBs through the
device internal communication buses.
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Battery Charger
(LIFEPAK 20 defibrillator/monitor) — The battery charger
is a constant current charger designed specifically to support the A07 NiMH
Battery selected for the device. NiMH batteries are not designed for trickle
charging, so the A09 AC Power Supply Module keeps track of the amount of
time the device has been operating from battery power. Charging is
performed following high-use incidents and periodically when the batteries
are not in high use. Charging can occur while the unit is powered on or while
the unit is powered off, depending on need. The battery charger is designed
to charge the internal battery, usually in less than two hours.
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