Ecg Recording And Front-End Processing - GE MAC 1200 Service Manual

ECG Recording and Front-End Processing

Revision D
Functional Description: PCB Control CS_CI
The patient input is classified as being cardiac floating and is defibrillation-proof.
The patient leads are connected with a 15-pin connector with a special form for the
specified and released patient cables for the MAC 1200 resting ECG analysis
system.
The main element of the ECG recording and front-end processing is a set of chips
comprising 3 ASICs. Pace detection is realized by a separate circuit.
Every disconnected electrode is detected by a special AC measurement, which
allows higher impedance between electrode and patient.
N common-mode compensation ensures suppression of interference, at the same
time serving to improve the in-phase suppression of the input electrodes.
To protect patients, the ECG recording and front-end processing are assembled as
floating components. Digital signals from and to the controller core are transmitted
via opto-electronic couplers. The floating supply ±5 V is generated by an isolated
flyback converter from the +5 V logic power supply.
MAC 1200 resting ECG analysis system
2012250-095
2-9