Instruction manual

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6 Input and Output 84
Holding Potential 0 V
These settings will create a protocol that delivers continuous square waves with 1V amplitude
and 100Hz frequency.
4 Press the Record button. The DAC will wait 100 milliseconds (the Delay value entered) and begin to
deliver 5ms pulses at the rate of 100 pulses per second. Each pulse will be 1V high. These pulse
parameters can be adjusted in any way with one exception, the pulse width cannot be longer than the
inverse of the frequency (or the period). In this example, the 100Hz square wave delivers 100 events or
pulses every second. Therefore, each single event or pulse must occur in 1/100th of a second, which is
a 10ms period. In this example, the pulse width cannot be longer than the period of 10ms or the pulse
will overlap the next pulse. The percentage of the period occupied by the pulse width is known as the
duty cycle and refers to the amount of time the output amplifiers are active.
An Example of a
Burst of Pulses
Use the settings listed for the example of continuous pulses to produce a short burst of pulses,
with one exception. Set the Number of Pulses to a number other than zero. If the number 10 is
entered in this box, the output from the DAC would wait the 100 millisecond delay from the Start
signal, deliver its 100Hz square wave of 5ms by 1V pulses as before, but stop when 10 pulses
had been delivered. A graphical representation of the two examples above is pictured in Figure
6-3 on page 84.
Figure 6-3: Continuous (top) and burst (bottom) of pulses that are the same amplitude, width, and frequency.
Train
Protocol
A train of pulses is more properly called a burst of pulses. Trains contain a specified Number
of Pulses, which occur a specified number of times (Number of Trains) at regular intervals
(InterTrain Duration). The train protocol is an extension of the pulse protocol so it is essential
to be familiar with the pulse protocol to use the train protocol.
Continuous output
Burst or Train output