Tektronix ADA400A Instruction Manual page 62

Replacement Parts
Theory of Operation
Input Coupling/
Input Protection
Refer to the Replaceable Parts section beginning on page 53 for a list of
customer replacement parts.
Figure 21 illustrates the functional blocks of circuitry from left to right in the
order of input to output. The darker boxes in the illustration designate front panel
controls and lines with arrows indicate the functional blocks that the controls
1M/ooQ
— Select
Input < High-Z
(4/4, 1/100}
{ Attenuator z
Input Protection
Figure 21: Diagram of the ADA400A Differential Preamplifier
Input Protection and
50
affect.
DC On/Off, "\" Overrange
Offset Coarse, Fine Oo Detect
Amplifier Amplifier
Low-Z f |
(+) Attenuator Low:nass Signal Out
100 Hz, 3 kHz, 100 kHz 1 MHz ot
able w15V
-15V
Scale Factor ad
[AC-GND-DC J [Gain 41,1, 10, 100 F——) Coding > Data
— — — Ground
Any signals on the inputs of the ADA4O0A Differential Preamplifier must pass
through the input protection and coupling circuits.
ADA4OOA Instruction Manual