Difference between revisions of "Programmable Chip EEG"

From OpenCircuits
Jump to navigation Jump to search
Line 17: Line 17:
  
  
Parts used in the PCEEG:
+
== Parts used in the PCEEG: ==
 
* [http://opencircuits.com/LT1168 LT1168 Programmable-Gain Precision Instrumentation Amplifier] is used to amplify the weak electric signals coming from the brain through electrodes attached to the scalp, etc.
 
* [http://opencircuits.com/LT1168 LT1168 Programmable-Gain Precision Instrumentation Amplifier] is used to amplify the weak electric signals coming from the brain through electrodes attached to the scalp, etc.
 
* Several [http://opencircuits.com/LT1114 LT1114 Low Power Precision OP-Amps] are used for amplification and filtering of the signal
 
* Several [http://opencircuits.com/LT1114 LT1114 Low Power Precision OP-Amps] are used for amplification and filtering of the signal

Revision as of 10:49, 20 July 2006

The Programmable Chip EEG

Welcome to the PCEEG Wiki, where everyone can add to this EEG brain-computer interface!

What it is and what it can be used for

The Programmable Chip EEG is a Modular Multi-channel electroencephalograph that could be used for a brain-computer interface, biofeedback....

The Programmable Chip EEG is programmable because it uses Digitally Programmable Potentiometers. They are used to set the Gain, frequency range, and can calibrate multiple analog boards for different EEG tests.

Discription of How it Works

The differential analog signal is amplified by the instramentation amplifier. Then the signal is amplified and conditioned by high pass and low pass filters.

The common mode signal is inverted summed and sent back to the body to decrese common mode signal thsi is done by the driver right leg circuit.

Band reject filters may be added soon in the future.

Then the analog signals are simultaniously digitized and the digital values can be clocked to the digital board.


Parts used in the PCEEG:

To reduce noise in the readout of the analog part of this circuit, a common-mode feedback is passed back into the body by the driver right leg circuit. Band reject filter may also be used (to reject, for example, 60Hz noise from nearby A/C power wiring).

The resulting analog signals will be passed into a digital circuit, based on the Cypress PSoC microcontrollers, which will digitize the signals, further process them, and provide an interface to a computer.