Keithley 7037, Инструкция по эксплуатации

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Service Information
6-9
Channel functionality test
1. As shown in Figure 6-6, connect the suspect input or
output channel to an output or input channel that is
known to be functioning properly. The internal 5V
supply must be used.
2. From the front panel of the mainframe, turn on (close)
the output channel. Verify that the display indicates that
the output channel is on (closed). Keep in mind that the
output can be high (positive) or low (negative) when the
channel is turned on, depending on the logic
configuration
3. Place the mainframe in the “read input channels” dis-
play mode. Verify on the display that the input channel
is off (open).
4. On the mainframe, turn off (open) the output channel
and verify on the display that the input channel turns on
(closes).
5. On the mainframe, return the instrument to the normal
display mode and verify on the display that the output
channel is off (open).
Figure 6-6
Testing an input or output channel
Special handling of static-sensitive
devices
CMOS and other high-impedance devices are subject to pos-
sible static discharge damage because of the high-impedance
levels involved. The following precautions pertain specifi
cally to static-sensitive devices. However, since many
devices in the Model 7037 are static-sensitive, it is recom-
mended that they all be treated as static-sensitive.
1. Such devices should be transported and handled only in
containers specially designed to prevent or dissipate
static buildup. Typically, these devices will be received
in anti-static containers made of plastic or foam. Keep
these parts in their original containers until ready for
installation.
2. Remove the devices from their protective containers
only at a properly grounded work station. Also, ground
yourself with a suitable wrist strap while working with
these devices.
3. Handle the devices only by the body; do not touch the
pins or terminals.
4. Any printed circuit board into which the device is to be
inserted must first be grounded to the bench or table.
5. Use only anti-static type de-soldering tools and
grounded-tip soldering irons.
Output Channel
Internal connections:
Internal voltage source (+5V) selected.
OUT
GND
Input Channel
IN
GND