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Agilent 34950A 64-Bit Digital I/O and Counter Module User’s Guide
34950A 64-Bit Digital I/O Module with Memory and Counter
Electrical Characteristics for Digital I/O Lines
The following simplified schematic shows the interface circuitry and
specifications
for each
of the 64 digital I/O lines:
Operating Considerations
See the
Introduction to the Plug In Modules
chapter of the 34980A
Mainframe User’s Guide
for detailed environmental operating conditions
for the 34980A mainframe and its installed modules. That guidance sets
maximum per channel current and power ratings at rated voltage for
pollution degree 1 (dry) and pollution degree 2 (possible condensation)
conditions, for the Digital I/O module.
VREF
OE
DOUT
DIN
EN
Zo = 10
Ω
2.5 pF
VTHREF
+5V
+
-
1M
14.7
26.1
10K
Vcc
+5V
+5.1V
I/O
1 of 64
Rpullup
Active Drive:
V
in
0V – 5V
V
out
(L)
0.24V < V
out
< 0.55V
4mA < I
out
< 24mA
V
out
(H)
1.6V < V
out
< 5V
-4mA < I
out
< -24mA
Open Collector:
V
out
0V – 5V
-4 mA < I
out
< -24mA
V
cc
(< 2V)
V
cc
(> 2V)
215
Ω
< R
pullup
< 1 k
Ω
215
Ω
< R
pullup
< 10 k
Ω
