Auxiliary Output - Metrix GX1010 Notice De Fonctionnement

4.2.2. Auxiliary Output

AUX OUT is a TTL/CMOS level output synchronous with MAIN OUT and with the same
symmetry. However, the phase of the AUX OUT can be varied with respect to the MAIN
OUT by changing the PHASE setting on the TRIGger edit menu.
4.2.2.1. Auxiliary Output Phase
0º 1 80º 36 0 º
frequencies. Changing AUTO settings is described more fully in the next section,
Waveform Generator Options.
The AUX OUT signal accompanying ramp, staircase and arbitrary waveforms is, by default,
always generated independently; phase shift is adjustable across the frequency range but
again clock jitter becomes increasingly significant at higher frequencies.
GX1010
S ine
S q uare
Trian g le
R a m p
A U X 0º
A U X 90 º
A U X 18 0º
The convention adopted for phase in this
instrument is illustrated in the diagram. 0°
is always the first data point in waveform
memory. On symmetrical waveforms 0° is
the rising edge 'zero-crossing' point for
sine, square, triangle and pulse waveforms;
0° is the start point of ramps, staircase and
arbitrary waves. When the phase is set to
0° the rising edge of the AUX OUT
squarewave is at 0° too. When the phase is
set to a positive value, e.g. +90°, the AUX
OUT squarewave follows MAIN OUT by
90°, when the phase is set to a negative
value AUX OUT leads MAIN OUT.
The phase is set by pressing the blue EDIT
key followed by TRIG to select the trigger
edit menu; the edit cursor is then moved to
the PHASE field using the FIELD keys.
PHASE can be entered directly from the
keyboard, using the +/- key to change the
sign if necessary, or by rotary control.
Above 30kHz the AUX OUT accompanying
sine, triangle, square and pulse waveforms
is automatically switched such that it is
derived from the comparator (driven by the
DDS sinewave) used to generate higher
frequency MAIN OUT squarewaves and
pulses; see the DDS Principles section for
further information. This ensures a jitter-
free AUX OUT signal up to the maximum
frequency of the generator but means that
phase shifting between MAIN OUT and
AUX OUT is not then possible. However,
this constraint can be removed by changing
the setting on the OPTions menu from AUX
OUTPUT=AUTO to AUX OUTPUT=LOW
FREQ; the AUX OUT signal then continues
to be generated independently, with phase
adjustable with respect to the MAIN output,
although the 1 clock (36ns) jitter will
become increasingly significant at higher
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