Throughout the evolution of the Digital Lynx system, Neuralynx developed three versions of Input Boards for electrophysiology data acquisition:
All three boards provide the same high performance features:
However, the main difference between these three Input Boards is the response of the low frequency signals below 1 Hz.
The DC Coupled Input Board had flat frequency response from DC to 7 KHz, but would saturate/clip when electrode offset voltages exceed 132 millivolts.
The AC Coupled Input Board used the same amplifier and A/D circuitry with a single pole 0.1 Hz High Pass Filter to block electrode input offset voltages with zero response at DC.
The Hybrid Input Board provides a lower noise “hybrid” design of the AC and DC input models using a very unique circuit design that featured:
The only trade-off of the Hybrid Input Board design is lower resolution at DC, which is normally not needed for neural recording.
The Hybrid Input Board offers the same 0.1 Hz HP filter of the AC Input Board with an attenuation limit of 90% at DC, thus giving the AC and DC responses described above.
The frequency response of the Hybrid Input Board is shown below. Notice the same flat response at 1Hz, the 0.1 Hz “knee” of -6 dB, and -18 dB response (~90% reduction) at DC.
The benefits of this unique Hybrid Input Board are: