4-6
MegaZoom Concepts and Oscilloscope Operation
Display Update Rate
Display Update Rate
In a na lo g o sc il l os co pe s, th e os ci ll os co p e i s b li nd wh i le th e e le ct ro n be am is re se t
to the left side of the screen. Thus, the update ra te of an analog oscilloscope
seems high because the blind or dead time of the analog scope is low.
Infrequent or random events that happen while the oscilloscope is blind are
missed, and thus not displayed. Oscilloscope users often assume that their
scope is capturing the entire waveform and that the update rate is perfect, when
the oscillosco pe display is ac tually missin g some events. If we could eli minate
this dead time, their assumption would be correct.
MegaZoom technology maintains high update rate by using parallel processing
and me mo ry se g me nt at io n. T he Me ga Zo o m o sc il lo sc op e fl ow s s am pl e s i nt o o ne
are a o f a cq ui si t io n m em or y, an d i n a no t he r a re a t he y a r e r ea d o ut an d pr oc es se d
into displayed samples. By doing this, the processing part of the update cycle
does n ot mi ss an y ev ents . Thi s re sult s in v ery f ast u pda te ra te an d a r espo nsiv e
user interface.