LFP Filter Main Amplifier

The TREC Local Field Potential Filter/Amplifier (LFP) is a multichannel, differential input main filter/amplifier for neurophysiological applications (e.g. extracellular recording with multiple microelectrodes). This LFP-Filter/Amplifier combines a band pass filter with variable cut-off frequencies and variable signal amplification on each channel in one instrument.

Key features:

  • 8 amplifier channels
  • Low-noise amplifier technique
  • Differential input amplifier
  • Individual gain settings from x50 up to x5000 (in different steps)
  • bandwidth 0.1 Hz ... 140 Hz (in different high pass filter steps)
  • AC coupled input circuit
  • Low noise technique
  • Integrated power supply
  • BNC Input and output
Dimensions and Weight: Depth (mm): 330mm
Width (mm): 450mm
Height (mm): 150mm
Weight (kg): 9kg
Power Supply: Supply voltage (V): 100-240V AC
Power Consumption (W): 30VA
Environmental conditions: Operating temperature range: +10°C to +40°C
Transport temperature range: +10°C to +40°C
Humidity: 20% - 80% RH (non-condensing)
Input data: Max. Filter input voltage: ±6V
Single Unit Activity (SUA) Bandpass Filter/Amplifier: Gain: 50, 100, 250, 500, 1000, 2500, 5000
Input impedance: 1M?//30pF
Low Pass cut-off [kHz]: 140Hz (fixed) other values on request
High Pass cut off [Hz]: 0.1 /1 / 10 / 20 Hz
Filter Characteristik: Butterworth
Input connector: BNC
Output Connector: BNC
Max. Output voltage swing: ±10V


Figure 1: 8 channel Local Field Potential Filter/Amplifier (LFP-08)

The LFP-Filter/Amplifier contains a high-gain, low-noise differential amplifier stage followed by low frequency and high-frequency filters. The amplifier has a differential Local Field Potential (LFP) bandpass filter–amplifier. The amplifier offers two levels of signal gain (x10, x100) in a first stage and 4 additional levels (x5, x10, x25 and x50) in a final amplifier stage (see Figure 2).

The amplifier has a band pass characteristic for Local Field Potentials (LFP) 0,1Hz…140Hz. The high pass cut-off frequencies are independently selectable 0.1 , 1 , 10 and 20Hz for low pass filter the cut off frequency is fixed at 140Hz.

Figure 2: Block diagram of one LFP-filter/amplifier section