LIFEPAK 15 Monitor/Defibrillator
Service Manual
Device Description
Functional Descriptions
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3
System connector interface
The device can be connected to external equipment for transmitting analog ECG signal output, data transmission, factory
test, Physio-Control field service data collection, and device configuration during field upgrade. Except for analog ECG
signals, all data communication at the system connector is at RS-232 levels.
The analog ECG signal output path consists of A01 System PCB components, including a digital-to-analog converter (DAC),
low-pass filter, and electrostatic discharge protection.
The digital communications output path consists of the following two components:
~ Dual universal asynchronous receiver/transmitter (DUART)
~ Level-shifter, used for converting device internal logic levels to RS-232 levels.
Display controller
Data for display on the device A11 LCD assembly originates from the A01 System PCB Display Controller made up of a
portion of the SBC and dedicated data driver/buffers. Screen fonts are stored in memory devices located on the A01 System
PCB.
Combined audio output
Originates from the A01 System PCB ASIC. System audio (voice prompts and alarm tones) from the ASIC returns to analog
form in an A01 System PCB DAC. System audio is filtered and routed to the A05 Interface PCB audio amplifier for
application to the W17 Speaker Assembly. Voice prompts are stored in memory devices located on the A01 System PCB.
Power PCB (A03)
The A03 Power PCB manages application of power to the device from the two Li-ion batteries. Additional functions include power
on/off control, “smart” battery communication, routing battery charge currents, battery voltage measurement, over-current
protection fusing, and serial communication of power status to the A01 System PCB.
A03 Power PCB operation centers around a power processor, which detects the presence of available power sources, selects a
power source for use by the device, and monitors their status (for example, low battery, replace battery, removal from the device,
etc.) and can apply charging currents from an attached power adapter to the batteries when connected.