ZOLL Propaq MD Rev A - Manual (Page 95)

Overview
9650-0807-01 Rev. A Propaq MD Service Manual 91
Defib CPLD
The Defib CPLD provides I/O control for the Pacer circuitry, the defibrillator charging and fire
control circuitry.
Pace/Defib (PD) Micro controller
The PD micro controller communicates with the PP processor on the monitor board to accept
commands to control the defibrillator and pacer. The PD micro controller controls the pacer
current and pulse timing and the defibrillation charging and waveform generation.
Communication between the Monitor and Defibrillator/Pacer boards is routed through the flex
cable connected to J106 of the defibrillator board and J38 on the Monitor board.
Charging Circuit
This is a high voltage step-up inverter that charges the Defib Capacitor. It provides electrical
isolation between the defib output and the system. The charging circuit will charge the Defib
Capacitor to up to 2775V. The Defib Capacitor is connected to the Defibrillator/Pacer board
through the 2-wire cable connected to J119.
Fire and Relay Circuit
The fire circuit employs high voltage switching devices to deliver a biphasic waveform to the
patient. Switching devices are utilized to produce a Rectilinear Biphasic
®
waveform. In
addition, relays are located between the fire circuit and the patient for electrical isolation. They
are engaged only when a valid command is set from the Defib CPLD.
Pacer
Pacer circuit delivers pacing pulses under control of the PD micro controller over an isolation
transformer. The pacer circuitry consists of an adjustable constant current power supply, pulse
timing, and current monitoring circuits.
Pads/Paddles ECG Preamplifier
This is a single channel ECG preamplifier paddle pick up that monitors the patient ECG signal
from the Defib paddles (or pads). It digitizes this signal and delivers it to the PP processor via
the PP interface. This preamp is a simplified version of the 3/5/12 Lead ECG utilized on the
Monitor Board.
Paddle Interface
Paddle interface circuitry detects analog voltage levels to decode switches and ID resistors of
the standard ZOLL paddles and internal paddles. The paddle set interface is connected to J115
of the Processor-Bridge-Pace PCB.
Printer
Propaq MD uses an internal thermal printer of 80 mm paper size that is built into the Defib
section of the enclosure. Communications with the printer is bi-directional, serial, (Main CPU
to/from printer) and complies with the software/hardware interface of the internal printer.
Communications are implemented using hardware Universal Asynchronous Receiver.
Transmitter (UART). The printer is controlled by the MP and is connected through a cable to
J46 and J49 of the Monitor board.