Data Sheet

LABCENTER ELECTRONICS LTD.
228
So the first simulation is complete. Looking at the traces on the graph, it’s hard to see any
detail. To check that the circuit is working as expected, we need to take some measurements.
Taking Measurements
A graph sitting on the schematic, alongside a circuit, is referred to as being minimised. To take
timing measurements we must first maximise the graph. To do this, right click on the graph and
select the maximise option from the resulting context menu.
This will open the graph in a new tab and change the menus and icons to include functionality
applicable to the graph.
On the left side of the screen is an area in which the trace labels are displayed and to right of
this are the traces themselves. When cursors are placed the data and delta values are
displayed at the bottom of the graph. As this is a new graph, and we have not yet taken any
measurements, there are no cursors visible on the graph, and the status bar simply displays a
title message.
The traces are colour coded, to match their respective labels. The OUT and U1(POS IP) traces
are clustered at the top of the display, whilst the IN trace lies along the bottom. To see the
traces in more detail, we need to separate the IN trace from the other two. This can be achieved
by using the left mouse button to drag the trace label to the right-hand side of the screen. This
causes the right y-axis to appear, which is scaled separately from the left. The IN trace now
seems much larger, but this is because Proteus has chosen a finer scaling for the right axis
than the left. To clarify the graph, it is perhaps best to remove the IN trace altogether, as the
U1(POS IP) is just as useful. Click right on the IN label and select Delete Trace. The graph now
reverts to a single, left hand side, y-axis.