1. Portable Real Time ECG Design
Presentation I
Yue Yin & Alex Szewczyk  
09/11/2014

2. Signals of Electrocardiography
Weak signals ranging from 0.5 mV to 5.0 mV
A dc component of up to ±300 mV (the electrode- skin contact)
A common-mode component of up to 1.5 V (the potential between the electrodes and ground)
Useful bandwidth of an ECG signal, depending on the application, can range from 0.5 Hz to 50 Hz
clinical ECG application has a bandwidth of 0.05 Hz to 100 Hz

3. Sources of noise Power-line interference: 50–60 Hz
Electrode contact noise (cause baseline drift)
Motion artifacts (shifts in the baseline)
Muscle contraction
Electromagnetic interference from other electronic devices (high frequencies)

5. For LT 1167
V for voltage range
- Voltage gain around 4.5
- G = 49.4k/Rg +1
- Rg = 14k
- High Common-mode rejection
- High input impedance

6. Reference:
Webster John G., Medical Instrumentation. Application and Design. 3rd edition, Wiley, 1998.