Notes and input from SP Devices
Introduction
SP Devices' digitizers are developed for high-speed and high resolution.
A typical example is the
ADQ14, which is a 14-bits
digitizer available as 4 channels 1 GSample/s or 2 channels at 2
GSample/s.
This page contains notes and inputs from SP
Devices about adding White Rabbit
functionality to digitizers.
WR enabling SP Devices digitizers
This discussion is focusing on developing White Rabbit compatibility for the digitizers. This development consists of 2 parts:
- controlling the digitizer and enabling the White Rabbit features
- build a system around the digitizer - White Rabbit solution
The first part is straight-forward. The digitizer has a clock reference
input for the 10 MHz clock reference. This will get the phase accuracy
needed.
The digitizer also has a sync input for the pps signal to control the
timestamp.
The second part, system built, is a more open question. We have identified two situations: multi-channel node and few channels node.
In the multi-channel mode, we assume a chassis with a large set of digitizers. For that we propose a WR-box that can provide timing reference to this array of digitizers. Then the digitizers operate as normal, but the timing is controlled from this WR-box.
In the single/few channels node, there are more possibilities, which mainly are related to the data transfer infrastructure.
- The digitizer is controlled by a local PC with an Ethernet connection for data transfer.
- The digitizer is controlled by a local PC which share the Ethernet connection for data with the timing control fiber connection of WR.
- The digitizer operate stand alone using the built in 10 GbE connection for high performance data transfer and the WR uses a separate 1GbE fiber for timing control.
Jan-Erik Eklund - 11 February 2016