LIFEPAK 15 Monitor/Defibrillator
Service Manual
Device Description
Functional Descriptions
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detection, and ECG sampling via analog-to-digital conversion (ADC). Results from the ADC process pass across the isolation
barrier to the A01 System PCB digital signal processor (DSP) for filtering and signal conditioning before being used by the
SBC CPU. ECG input is through the parameter bezel W07 ECG Connector Cable.
IP / Temperature front end
The invasive pressure (IP) circuitry processes the input signal from a disposable IP transducer through the IP input
connectors on the device parameter bezel. Two input connectors are provided for simultaneous monitoring of two IP
channels. The W33 Invasive Pressure Harness provides the connection from the parameter bezel to the A01 System PCB,
where the IP/temp preamplifier circuitry is located.
The IP/temp preamplifier is isolated from the AC power ground by the ECG preamplifier iso-barrier. The transducer drive
circuitry supplies a positive 2.5 V and a negative 2.5 V excitation voltage to the resistive bridge-type transducer. The output
signal from the transducer is conditioned by a low-pass filter at the input of an instrumentation amplifier, which amplifies
the signal approximately 400 times. The signal is then multiplexed to the A-D converter, digitized, and then sent serially
across the iso-barrier for DSP processing and display.
The temperature circuity processes the input signal from a disposable temperature probe through the external adapter cable.
The temperature adapter cable connects to the connector below the ECG connector on the parameter bezel. The W35
temperature connector cable provides the connection from the parameter bezel to the A01 System PCB.
Printer controller
The device uses a 100-mm thermal array printer. The A01 System PCB printer controller governs motor speed, adjusts print
strobe pulse width, senses paper presence and door closure, senses printhead temperature, and provides the data to be
printed. Printer fonts are stored in memory devices located on the A01 System PCB.
Real-time clock/non-volatile RAM (RTC/NVRAM)
The RTC/NVRAM maintains the date and time and provides storage for device user setups. The RTC/NVRAM is powered by a
lithium coin cell battery.
