Appendix 2. Trigger Input/Output - Neurosoft Neuron-Spectrum-1 Technical Manual

Appendix 2. Trigger Input/Output

The side panel of Neuron-Spectrum digital system provides a trigger socket for the
attachment of stimulators produced by the other manufacturers to the digital system.
The devices connected to the trigger socket must have protection class against
electrical shock according to IEC 60601-1.
Cables for connection of devices produced by the other manufacturers are not
included into delivery set and must be produced according to the recommendations
stated in the present Appendix.
The trigger socket is a double-pin plug of 2.5 mm diameter. It is used as a trigger input
to synchronize the program with external stimulus and as trigger output to transfer the
pulse synchronously with the work of internal stimulators.
The socket schematic and triggering pulse parameters are described on Fig. 14.
If the trigger input is used, then negative polarity pulse TTL not less than 5 µs must be
at the input. Pulse droop will be considered as the beginning of synchronization. The
synchronization signal is also generated by short-circuit of input to common wire for
not less than 5 µs.
Permanent short-circuiting of input to common wire makes the signal
transmission from internal stimulators impossible.
When the trigger output is used, with each stimulus, negative polarity pulse of TTL
level appears at the connector which fall corresponds to the beginning of the stimulus.
Pulse duration for photic, auditory and pattern stimulation is from 500 up to 600 µs at
the trigger output (Т on Fig. 14).
1 2
Т
Fig. 14. Socket schematic and specifications of triggering pulse.
The external stimulators connected to the trigger input must be used in the following
order:
1. Connect the external stimulator to the trigger input using a cable.
Trigger input
Trigger output
5 V
Appendix 2. Trigger Input/Output
+ 5 V
Socket EP253
1
2.5 mm
2
43