Keithley 7021, Инструкция по эксплуатации

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Digital I/O Configuration
3-2
Each output channel uses a fly-back diode for protection
when switching an inductive device, such as a solenoid coil.
This diode diverts the potentially damaging fly-back voltage
away from the driver.
CAUTION
Failure to set J201 to the V
ext
position
when using external pull-up voltages
may result in damage to the output
drivers.
Controlling devices using pull-up resistors
When interfacing outputs to high-impedance devices (i.e.
logic devices), internal pull-up resistors are used to achieve
the appropriate logic level. Figure 3-2 shows the output con-
figuration using the 10k
Ω
pull-up resistor (R
P
).
The configuration in Figure 3-2 uses the internal 5V source
as the high logic level. If you need a higher logic level, you
can place the jumper in the alternate position and apply an
external voltage (via V
EXT
).
Figure 3-2
Output configuration using pull-up resistance
Driver
Jumper
5V
V
EXT
Logic
device
7021
R
P
10k
Ω
GND
Or
gate
A
B
Y
+V
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