Tektronix PG502 Instruction Manual page 10

Operating Instructions-PG 502
t--
Pulre Period
T = ,/Rate
Duly Facto* = Pulse DurationlPulsa Period
excluding unwanted aberrations or overshoot. Measurement
points are at 50% of the pulse duration time (pulse high
IevelJ and on rhe baseline (pulse low level) at 50% of rhe off
time (the pulse period minus the pulse duration).
Aberrations. Unwanted deviations or excursions in the
pulse shape from an ideal ~uare corner and flat top, i.e..
overshoot. undershoot or rounding, ringing, and tilf or
dope.
Baseline. The quiescenf DC voltage reference level of
the pulse waveform,
Complementary Pulse. Normal pulse with high and low
levels inrerchanged. Pulse on-time becomes pulse off-time.
Duty Factor. Sometimes referred to es duty cycle. The
ratio of pulse duration to period, or the product of pulse
duration and pulse repefifion rate. Duty fector in % =
Duration/Period X 100.
Falltime. The time interval. et rhe pulse trailing edge,
for the pulse amplitude to fall from the 90% amplitude
level to the lOPA amplitude level.
Flatness. The absence of long rerm variations to the
pulse top; excluding overshoot. ringing or pulse rounding.
Sometimes referred to a5 tilt or slope.
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High Level. The most positive value of a pulse, regard-
less of unwanted aberrations or overshoot, measured at a
point that is located at 50% of the pulse duration.
Low Level. The most negative value of a pulse. regard-
less bf unwanted aberrations or overshoot, measured at a
point fhat is at 50% of the off time.
Offset. A DC potential of either polarity applied to the
waveform to bias the baseline to an amplitude other than
zero.
Overshoot. The short term'pulse excursion (0; tran-
si@nT) above the pulse top or below the baseline, which is
simultaneous to the leading or trailing edge of the pulse.
Period. The time interval for B full pulse cycle. inverse
of frequency or repetition rate, or the interval between
corresponding pulse amplitudes of two consecutive un.
delayed or delayed pulses. Generally measured between the
50% amplitude levels of two consecutive pulses.
Preshoot. A transient excursion rhat precedes the Step
function. II may be of the same or opposite polarity as the
pulse.
Pulse Duration. The time interval between the leading
and trailing edge of a pulse at which rhe instantaneous
amplitude reaches 50% of the peak pu,lse amplitude.
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