Scuba2 Telescope

Here are pictures of some the cards I worked on for the Scuba2 telescope. These cards were part of the electronics package used to measure the telescope sensor array. Both of them are based around the now ancient Altera Stratix FPGAs. The card below was the controller for the whole package. This card has 2 FPGA configuration memories to make sure it could still boot if a remote update failed.

Scuba2 clock card
Scuba2 clock card

This second card is more interesting. Each card had 8 really sensitive analog channels consisting of an amplifier chain and an ADC. Each ADC had a dedicated data bus to the FPGA so that all 8 channels could be converted simultaneously and as fast as possible. All those data bus lines meant that it was a real challenge to meet the analog sensitivity/noise requirements and to also route the board. In the end it took 14 layers and partial vias were still needed. This is the most expensive board I’ve ever designed – the circuit board alone cost more than complete products I’ve designed in the past!

Scuba2 readout card
Scuba2 readout card

I did all of the digital design work for these cards and also supervised and reviewed the PCB layouts which were done by another company.