The ADC is used as an on-board oscilloscope.
During normal WorldFIP operation the ADC will be deactivated with the
related power supplies turned off.
In case of a failing segment, the macrocycle would change to a simple
predefined one (ex. a presence variable request to nodes 1..255) and the
ADC would be turned on and connected to the secondary side of the
To simplify the design of the board, the same ADC used in the FMC-ADC
has been selected.
Figure 1 shows the frame on the secondary side of the transformer. Each
signal of the differential pair is at 2.3 +-1.5V.
The calculated rising time is 70 ns for a consumed frame and 10 ns for a
produced one; through a simple rule of thumb this translates to a
bandwidth of 35 MHz.
The ADC on the board allows input range +-5.26 V (front-end) and samples
> Figure 1: probing on the FieldTR secondary side
Finally it was decided to develop a version (V3) without the ADC board,
due to high component and maintenance costs.