User`s guide

Bias Point Analysis 2
-7
Usin
g
the Bias Information
Displa
y
You can display bias information on your schematic, including
voltages for all nets and currents into all pins. You can also
control which nets and pins have voltage and current
measurements displayed at any given time.
To displa
y
bias volta
g
e information at all nets
1
In Schematics, make the
clipper.sch window active.
2
If the Simulation toolbar is not displayed, do the following:
a
From the View menu, select Toolbars.
b
Select (
✓) the Simulation check box, then click Close.
3
If voltages are not displayed, then do the following: On the
Simulation toolbar, click the Enable Bias Voltage Display
button. DC bias point voltages appear at all nets
(Figure 2-4).
Fi
g
ure 2-4
Clipper Circuit with Bias Point Voltages
Displayed
Because the diodes are both reverse biased (off), and the input
source Vin is 0V (a short circuit to ground), the bias point is
dependent only on the values of Vcc, R1, R2, and R3.
The bias information display
commands are also available
from the Analysis menu by
pointin
g
to Display Results on
Schematic.
You can move an individual
volta
g
e label as needed by
selectin
g
and dra
gg
in
g
it. When
you select a volta
g
e, the wire
with which the volta
g
e is
associated is hi
g
hli
g
hted for
clarity. Volta
g
e labels remain
wherever you move them unless
you delete or move the
associated wire.
Individual currents have the
same properties as volta
g
es
except that they are associated
with device pins and the
association is illustrated by
arrows.
The volta
g
e at net Mid is in
a
g
reement with manual
calculation
where
Correct, expected bias point
analysis results provide
assurance of proper circuit
connectivity.
VMid
()
Req
R2 Req+
-----------------------
Vcc
×
=
Req
R1 R3
×
R1 R3+
--------------------=