LIFEPAK 20/20e Defibrillator/Monitor
Device Description
Functional Description
(continued)
A04 Therapy PCB
controls the pacing and defibrillation therapy features.
The primary communication between the A04 Therapy PCB and the remainder
of the device is through the data bus. A microprocessor and digital memory
make up the central processing unit (CPU) that manages communication with
the A01 System Control PCB.
The major subsystems on the A04 Therapy PCB are as follows:
■
Power Supplies
— The A04 Therapy PCB uses SW_VBatt (switched
battery voltage) from the A03 Power Module to originate five power supply
voltages for use throughout the PCB as follows:
– +5 V logic power to drive the CPU microprocessor and memory
– ±15 V analog power for the pacing and therapy drive circuit
– Patient-isolated 5 V analog power for the pacing and therapy circuits
– Patient-isolated 15 V analog power for the pacing and therapy circuits
– Patient-isolated 30 V analog power for the pacing and therapy circuits
(Continued on next page)
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