INT7 A/D Converter
6 Tables and specifications
Fig 39: Standard INT7-compatible cable for two detectors
6.2 Parameters of Digital Inputs and Outputs
Digital Outputs
The card contains eight digital TTL outputs (OUT1-OUT8) with a maximum
permissible current of
20 mA
at both levels. The first four outputs are also
equipped with relay contacts (OUT1S1/OUT1S2- OUT4S1/OUT4S2).
The maximum permissible current is
100 mA
, the maximum- switched
voltage is
100 V
and the contact resistance is
150 mΩ
. The relay is
onstate (closed) when there is a
LOW
level of a relevant digital output.
Digital Inputs
The card contains 4 digital TTL inputs IN1 to IN4. The first two inputs are
also
equipped
with
an
optoelectronic
isolator
(M1S+/M1S-
and
M2S+/M2S-). The excitation current is
5 mA
and corresponds to input level
LOW
.
The LED of the isolator is directly connected to the connector.
Caution:
A resistor must be inserted (e.g. in the connector) to restrict the diode
current to
10 mA
max.
To suppress the contact bouncing, the digital inputs are equipped with
monostable toggles that prolong any change affecting the input to at least
200 ms
(to ensure that the station is able to detect it).
A pulse with duration of at least
1 ms
is necessary in order to excite the
toggles.
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