Biosignal amplifier for the USBDUX-sigma

The amplifier operates at a gain of either G=500 (preferred) or G=2000. If you have an EEG of approx 100uV you'll get 50mVp-p or 200mVp-p at the A/D converter. This means that especially for G=500 there is enough headroom to accommodate baseline shifts due to cable movements and DC drift while at the same time the 24 bit resolution of the USB-DUX-sigma guarantees that the signal is still digitised at high preceision. At this gain also single channel ECGs can be measured, for example Einthoven II.

eeg-1.0.zip contains the EAGLE files and the BOM. The PCB but it can be ordered from Beta Layout by sending them the .brd file. They can also fit the components. All components can be ordered from Farnell. Simply copy and paste the BOM into their "quick paste" order form.

for a quote for the complete kit or the assembled board.

This amplifier was used in depth of anaesthesia research:

A proof of concept evaluation of the electroencephalophone as a discriminator between wakefulness and general anaesthesia. Glen, J., Porr, B., Hamilton, R., Tait, L. (2013) British Journal of Anaesthesia.