DS4 Bi-Phasic Current Stimulator

DS4 Bi-Phasic Current Stimulator


Manufacturer's Net List Price


  • External voltage control permits software defined waveforms
  • Isolated constant current output for low noise
  • Minimal zero crossing distortion
  • Inactivity sensor significantly reduces leak currents
  • Battery test sockets
SKU: DS4 Category:



The DS4 Bi-Phasic Current Stimulator has been developed to meet the needs of life scientists who require a stimulus isolator that can output a bi-phasic isolated constant current stimulus in response to an external command voltage signal, provided by a computer DAC via software. Such a requirement is already met by our NeuroLog System in the form of the NL512 Biphasic Buffer and NL800A Stimulus Isolators, but the DS4 Bi Phasic Stimulator provides our first standalone device to meet this need.

Unique “Inactivity Sensor” Prevents Unwanted DC Stimulation

One of the problems with stimulators that make use of an external voltage source to define a stimulus waveform is that small offsets or noisy baseline signals from the DAC’s used to drive them can result in unwanted battery drain or perhaps worse, low amplitude stimulation. The DS4 Bi Phasic Stimulator uses a special “inactivity sensor” to monitor the input voltage and disable the DS4 output if this voltage falls within 0±0.15% of the full-scale value for a user selectable time period of 100ms, 200ms, 1s or 2s. Unlike other devices which only produce an output when the input voltage exceeds a threshold value, this “inactivity sensor” reduces battery usage and damaging “leak currents” during infrequent stimulation, while at the same time maintaining low levels of zero crossing distortion for repetitive waveforms.

The DS4 Stimulator uses an external DC power supply to power the input control circuitry and readily available/inexpensive batteries to provide the opto-isolated stimulus voltage source. The DS4 can be fitted into a 19″ rack mounting frame (D121-11) which can hold up to two DS2A’s, DS3’s DS4’s or DG2A’s.

Contact us on 01707 328347 or via email at sales@digitimer.com for further information regarding the DS4 Bi-Phasic Current Stimulator.

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Product Information

DS4 Bi-Phasic Stimulus Isolator

Publications which cite use of the Digitimer D185 can be found on Google Scholar.





  • Power Supply Adaptor
  • Mains Lead
  • Operator’s Manual
  • One set of batteries
  • Pair of output plugs (NL985P)



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