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Chapter 7 Tutorial
Low-Level Signal Multiplexing and Switching
4
7
The 34901A and 34902A multiplexers have an additional relay, called a
bank switch
or
tree switch
, which helps reduce channel-to- channel noise
(C
adj
). The multiplexer channels are divided into two banks. The bank
switch isolates one bank of channels from the other, effectively removing
any parallel adjacent capacitance from the isolated bank. During a scan,
the instrument automatically controls the bank switches.
If you are not using all of the channels on the multiplexer, divide the
input signals equally between Bank 1 and Bank 2. For example, if you
are multiplexing eight channels using the 16-channel multiplexer, use
four channels in the lower bank and four channels in the upper bank. For
even better noise immunity, leave one unused, grounded channel
between each input channel.
Module
Bank 1
Bank 2
34901A
Channels 1 through 10
Channels 11 through 20
34902
Channels 1 through 8
Channels 9 through 16
34908A
Channels 1 through 20
Channels 21 through 40
Source
Source
Source
Bank 1
Bank 2
Channel
DMM
Bank Switch
Bank Switch
C
adj
C
adj
Source
Switch
Channel
Switch
34970A Refresh UG.book Page 305 Wednesday, February 17, 2010 12:34 PM
Summary of Contents for 34970A
Page 16: ...16 34970A Refresh UG book Page 16 Wednesday February 17 2010 12 34 PM ...
Page 20: ...34970A Refresh UG book Page 20 Wednesday February 17 2010 12 34 PM ...
Page 21: ...1 1 Quick Start 34970A Refresh UG book Page 21 Wednesday February 17 2010 12 34 PM ...
Page 39: ...2 2 Front Panel Overview 34970A Refresh UG book Page 39 Wednesday February 17 2010 12 34 PM ...
Page 59: ...3 3 System Overview 34970A Refresh UG book Page 59 Wednesday February 17 2010 12 34 PM ...
Page 87: ...4 4 Features and Functions 34970A Refresh UG book Page 87 Wednesday February 17 2010 12 34 PM ...
Page 217: ...5 5 Error Messages 34970A Refresh UG book Page 217 Wednesday February 17 2010 12 34 PM ...
Page 241: ...6 6 Application Programs 34970A Refresh UG book Page 241 Wednesday February 17 2010 12 34 PM ...
Page 254: ...254 34970A Refresh UG book Page 254 Wednesday February 17 2010 12 34 PM ...
Page 255: ...7 7 Tutorial 34970A Refresh UG book Page 255 Wednesday February 17 2010 12 34 PM ...
Page 324: ...324 34970A Refresh UG book Page 324 Wednesday February 17 2010 12 34 PM ...