LIFEPAK 20/20e Defibrillator/Monitor
Device Description
Functional Description
(continued)
A02 Patient Parameter
PCB
collects ECG and SpO2 patient data, with the
exception of the paddles ECG data, and provides preprocessed data to the
system controller for AED and R-wave algorithms, alarm control, operator
display and printout, and storage. Algorithms performed on the data before it is
sent to the A01 System Control PCB include leads-off detection and internal
pacer detection. A digital signal processor (DSP) with digital memory makes up
the central processing unit (CPU)
that performs these algorithms.
Communication is provided to the A01 System Control PCB through the data
bus.
The major subsystems on the A02 Patient Parameter PCB are as follows:
■
Power Supplies
— The A02 Patient Parameter PCB uses switched power
from the A04 Therapy PCB with dc power from the A07 Battery to originate
three power supply voltages for use throughout the PCB as follows:
– +3.3 V logic power to drive the CPU digital signal processor and memory
– +5 V analog power to drive the A06 OEM Interface PCB
– ±5 V patient-isolated supply to drive the ECG pre-amp
(Continued on next page)
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