Gated Modes - TTI TGP110 Manual De Instrucciones

Gated Modes

When Gated is selected on the Run-Triggered-Gated switch the generator produces a train of
pulses which starts after a delay from the leading edge of the gating signal. The last pulse is
completed (i.e. normal pulse width) when the gating signal ends except for Square mode which is
terminated synchronously with the gating signal. The gating signal is derived from either an
external signal applied to the TRIGGER/GATE IN socket or by pressing the Manual button. The
delay from the leading edge of the gating signal to the first pulse is approximately 20% of the
PERIOD range setting plus 80ns; the vernier setting has minimal effect.
The PERIOD, PULSE WIDTH and PULSE DELAY controls set the pulse train parameters in
exactly the same way as for Run mode according to which FUNCTION/MODE position is
selected. Refer also to the timing diagram.
COMPLEMENT
The Complement switch inverts both AUX OUT and MAIN OUT. It is most useful in generating
jitter-free large mark:space ratio waveforms which cannot be obtained in Normal mode. The
"space" instead of the "mark" is determined by the PULSE WIDTH controls in this mode.
MAIN OUT
The amplitude of MAIN OUT is controlled by the 2-position range switch and the AMPLITUDE
control which provides continuously variable adjustment within each range.
The output has a 50Ω source impedance and is designed to operate into a 50Ω load under which
condition the two ranges are 50mV to 500mV and 500mV to 5V. Good quality 50Ω coaxial cables
should be used. If the cable is not terminated with 50Ω, greater amplitude can be achieved but
cable reflections will cause aberrations on the waveform.
AUX OUT
The AUX OUT provides a TTL/CMOS compatible waveform with the same timings as MAIN OUT.
This output occurs approximately 15ns before MAIN OUT.
SYNC OUT
SYNC OUT provides a TTL/CMOS compatible pulse of typically 30ns duration which occurs
approximately 40ns before MAIN OUT in all Pulse modes. In Square mode the SYNC pulse
occurs approximately 10ns after the MAIN OUT leading edge.
TRIGGER/GATE IN
The TRIGGER/GATE IN is the control input for the triggered and gated modes which have
already been described. The input is a Schmitt trigger which can handle any wave shape from
DC-10MHz with >2V input level.
Do not apply external voltages exceeding ± 10V.
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