Model 7701
19
Biasing and measuring DUT (dual multiplexing)
This application demonstrates how to use the Model 7701 as a dual multiplexer to bias and measure 16
DUT. An external source powers DUT, while the DMM of the Model 2700/2750 measures the output of
the DUT. To prevent overloading of the external source, each DUT is powered (and measured) sepa-
rately.
shows the connections for this application. The external source is connected to the Multi-
plexer 2 terminals of the switching module, and DUT is connected to channels 1 through 16. Channels
17 through 32 are used to connect external power to each DUT.
For this application, channels 33, 34, and 35 are to be controlled as follows:
•
Closing channel 33 isolates the input measurement channels 1 through 16 (Multiplexer 1) from
the external source channels 11 through 20 (Multiplexer 2). It also connects the DUT to the
external source. This channel must remain closed while testing DUT.
•
Opening channel 34 isolates the external source from the backplane of the Model 2750. This
channel must remain open while testing DUT.
•
Closing channel 35 connects an input channel (1 through 16) to the DMM. This channel must
remain closed while testing DUT.
In
, channels 1 and 17 are closed to test DUT 1. The test for the other DUTs is similar except
that different source and measure channels are closed. Closed channels for each DUT test are listed as
follows:
Tested Device
Closed Channels
Tested Device
Closed Channels
DUT 1
1, 17, 33, and 35
DUT 9
9, 25, 33, and 35
DUT 2
2, 18, 33, and 35
DUT 10
10, 26, 33, and 35
DUT 3
3, 19, 33, and 35
DUT 11
11, 27, 33, and 35
DUT 4
4, 20, 33, and 35
DUT 12
12, 28, 33, and 35
DUT 5
5, 21, 33, and 35
DUT 13
13, 29, 33, and 35
DUT 6
6, 22, 33, and 35
DUT 14
14, 30, 33, and 35
DUT 7
7, 23, 33, and 35
DUT 15
15, 31, 33, and 35
DUT 8
8, 24, 33, and 35
DUT 16
16, 32, 33, and 35
