Specifications

D1600 Data Sheet B-2
Figure B-2. Controlling Hysteresis For Positive-Going Signals
This connection is used for unipolar positive-going frequency signals. The
hysteresis is centered around a +2.5V switching level. If R is left open, the
switching levels are +3V and +2V, or 2.5V ±0.5V. If R is shorted, the
hysteresis decreases with resulting switching levels of 2.5V ±5mV. Any
hysteresis value from ±5mV to ±0.5V may be obtained by selecting an
appropriate value for R. Figure B-2 shows the relationship between the
hysteresis and R.
The input comparator may be setup for comparisons around zero volts by
using the connections in Figure B-3. This connection is useful for AC or
bipolar signals. Since the input section is isolated, the +2.5V pin may be
connected to any signal with a common-mode voltage up to 500V. With the
hysteresis control connected as in Figure B-3, the switching points occur
symmetrically on either side of the +2.5V level. Since the low side of the input
signal is connected to the +2.5V pin, the switching points appear to be
symmetrical to zero, as referenced to the input signal. The hysteresis may
be varied from ±5mV to ±0.5V as shown in Figure B-2.
R V
switching
± V
hysteresis
Open 2.5V ± 0.5V
ØΩ 2.5V ± 5mV
For V
hysteresis
>5mV and
<0.5V:
34 V
hysteresis
R (in KΩ) =
0.5 -V
hysteresis