Datex-Ohmeda S/5 monitors
Document No. 8001013-1
6
2.2.1
PT board
RS485 driver
for data
RS485 driver
for module
reset
Power-up
reset
Power
,
non-isolated
section
ECG OUT
PRESSURE OUT
Patient Isolation
Opto
Isolation
Isolation
transformer
Power,
isolated
section
Module bus connector, D25
Microprocessor
section
A/D converter
INV.pressure
measuring
unit
Temperature
measuring
unit
Keyboard
to output connector
to pressure
sensor
to temperature
sensors
non-volatile
memory
Figure 3
PT board block diagram
ECG and pressure signal prosessing
The PT-module has the Signal Out connector, for output of analog ECG and pressure signals.
The analog ECG-output signals are made by detecting the pulse-width modulated (PWM) ECG
signal of the module bus. The module detects the presence of the pacemaker pulses by following
the ECG module. Every time the pacer pulse has been detected, the microprocessor of the M-PT
module generates a 2.5 ms pacer pulse which is added to the analog ECG signal.
The PRESSURE OUT signal is generated from the P3 invasive pressure signal of the M-PT module.
