Keithley 7035, Инструкция по эксплуатации

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Service Information
5-16
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 7035 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.
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.
Principles of operation
The paragraphs below discuss the basic operating principles
for the Model 7035 and can be used as an aid in troubleshoot-
ing the card. The schematic drawings of the Model 7035 card
are shown on drawing numbers 7035-106 and 7035-176 at
the end of Section 6.
Block diagram
Figure 5-8 shows a simplified block diagram of the
Model 7035. Key elements include the relay drivers and
relays, as well as the ROM, which contains card ID and con-
figuration information. These various elements are discussed
in the following paragraphs.
Figure 5-8
Model 7035 block diagram
To Mainframe
CLK
Data
Strobe
Enable
Relay
Drivers
U101-
U105
Relays
User connections
ID CLK
ID DATA
ROM
U107
+3.5V (Steady State)
+5.7 (
≈
100 msec during
relay actuation)
Relay
Power
Control
Q101, Q102
U106, U108
+6V,
To Mainframe
+15V