Keithley 7070, Инструкция по эксплуатации

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OPERATION
2-6
The DIGITAL COMMON BUS provides a common connec-
tion for on-card active circuits using the mainframe’s +5V
supply.
2.3.9 +5V and +6V Supplies
The +5V supply can be used to power user-installed digital
circuits mounted on the Model 7070 breadboard. Note that
the m5V supply current for the card is 500mA.
The +6V supply can be used to power user-installed relays.
The maximum current available from the +6V supply 2.9A;
this value assumes that no other cards are installed in the
mainframe. See paragraph 2.5.4 for a detailed discussion of
power supply limitations.
2.3.10 Chassis and GND Connections
The two screw terminals adjacent to the input/output con-
nectors are at chassis ground potential and can be used to
connect cable shields to chassis ground. An additional chas-
sis ground pad is located on the lower rear corner of the
card. The GND pad located at the lower rear terminal is con-
nected to digital common.
2.4 EXTENDER CARD OPERATION
NOTE
This section does not apply to the Model 7070-PCA.
One of the two functions of the Model 7070 is used as an
extender card for troubleshooting or bench-top testing of
other matrix cards. The following paragraphs discuss set-
ting up the unit as an extender card, connecting the ribbon
cables, and connecting other cards to the extender board.
2.4.1 Selecting the Extend Function
In order to use the Model 7070 as an extender card, the
CARD FUNCTION switch must be in the EXTEND posi-
tion, as shown in Figure 2-2.
NOTE
If relays are mounted on the card, disconnect the
+V relay bus from the relay supply voltage before
using the Model 7070 as an extender card. Other-
wise, any on-card relays will be energized when
accessing the card slot.
Figure 2-2. Extend Function Jumper Selection
2.4.2 Ribbon Cable Connections
Three 10-foot ribbon cables attached to an extender board
are supplied with the Model 7070. In order to use the
Model 7070 as an extender card, these cables must be con-
nected to the on-card connectors, as shown in Figure 2-3.
The widest cable should be routed through the upper cable
clamp, while the two narrower cables should be routed
through the lower cable clamp (remove upper half of clamp
Þ rst). After making connections, secure the ribbon cables
with the clamps. Also dress the cables with the supplied
cable clips where convenient.
Card Function
Extend
Local