GE B30 Technical Reference Manual page 48

B30 Patient Monitor
RESPIRATION
MEASUREMENT
AMPLIFIERS
RS 485
COMMUNICATION
ISOLATION
Figure 19
ECG input unit
The ECG input unit consists of the front panel connector and the ECG input connector board
with the high voltage protection resistors. The connector for the ECG cable is a green 11-pin
rectangle shaped connector.
Input protection and filtering
The input protection is implemented with high voltage protection resistors in the ECG input unit
and with protection diodes in the ECG board. The input filtering for ECG measurement is done
with passive RC filtering.
ECG preamplifiers
The buffer amplifiers are used for each lead. The "Leads off" detection is implemented by
measuring the output level of the input buffer amplifiers with the A/D converter of the CPU. The
ECG signals are measured using differential amplifiers.
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Document no 2044677-001
PATIENT AND ECG ELECTRODES
ECG CABLE
- ECG LEAD SET
- ECG TRUNK CABLE
ECG INPUT UNIT
- ECG CONNECTOR
- INPUT PROTECTION RESISTORS
INPUT PROTECTION DIODES FOR ECG & RESPIRATION MEASUREMENT
INPUT FILTERING FOR ECG & RESPIRATION MEASUREMENTS
RESPIRATION
MEASUREMENT
CURRENT SUPPLY
POWER SUPPLY
ISOLATION
MODULE BUS CONNECTOR
ECG measurement block diagram
ECG
PREAMPLIFIERS &
RLD CIRCUIT
BASELINE
RESTORATION
ECG CPU
NV
MEMORY
ECG BLOCK DIAGRAM
LEADS OFF &
PACER &
DEFIBRILLATION
DETECTION