Application Circuits
(Continued)
DS100080-25
FIGURE 2. Inverting Comparator with Hysteresis
Non-Inverting Comparator with Hysteresis
Non inverting comparator with hysteresis requires a two re-
sistor network, and a voltage reference (V
ref
) at the inverting
input. When V
in
is low, the output is also low. For the output
to switch from low to high, V
in
must rise up to V
in1
where V
in1
is calculated by
When V
in
is high, the output is also high, to make the com-
parator switch back to it’s low state, V
in
must equal V
ref
be-
fore V
a
will again equal V
ref
. V
in
can be calculated by:
DS100080-22
The hysteresis of this circuit is the difference between V
in1
and V
in2
.
∆V
in
= V
cc
R
1
/R
2
DS100080-23
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