TAMC900-A1 User Manual Issue 1.0.2
Page 9 of 17
4 Analog Inputs
The TAMC900-A1 provides access to the analog inputs of the eight ADCs of the TAMC900. As signal
conditioning, it provides a differential amplifier with Gain = 1 for each analog input.
The figure below shows one analog input path of the TAMC900-A1.
ANA and ANALOG_INx- build one analog input of the TAMC900-A1, and the resistors R
I
and R
F
set the gain of the signal conditioning (gain = 1).
- +
+ -
3.3 Volt
GND
R
I
R
I
R
F
LTC6404
Output to TAMC900
R
F
Signal Conditioning
ANALOG_INx-
ANA
AIN_x-
AIN_x+
Analog Input
Figure 4-1 : Analog Input Block Diagram
An Infiniband connector (FCI 58368-111010 or compatible) is used for the analog inputs.
A differential signal is composed of two (ground referenced) single
ended signals.
For each analog input, you need to connect three signals:
AN, ANALOG_IN-, and GND
4.1 Input Voltage Range
The common mode voltage range of the analog inputs is 0 – 3.3 Volt, and independent from the output
common mode voltage.
The maximum differential input voltage V
INDIFF
(difference between ANA and
ANALOG_INx-) should be limited to ±1.0 Volt, because this is the input range of the ADCs on the
TAMC900.
Please refer to the LTC6406 data sheet for more details. The data sheet is part of the Engineering
documentation.
For optimal performance, do not exceed the maximum differential
input voltage range of the TAMC900 ADCs.
