Actually, we can fit a lot to single FMC Look here: https://scontent-waw1-1.xx.fbcdn.net/hphotos-xpa1/v/t1.0-9/66620_1649317561668_2595483_n.jpg?oh=982ee50c1a1d8ecc444346c9eae1fe1c&oe=578FA78C I managed to place there 16 AFEs, 16x130MHz ADCs, 16 buffers, FPGA, SDRAM, quad DAC with amplifier, SMPS supply. The PCB has 4 layers. Of course in case of RF stuff we need shielding, but we can fit there 2 JESD ADC/DACs, which have very simple interface and half of the FMC will be still available for 2 RF up or downconverters and fitlers. Here is example that presents how much space is taken by the shielding/heat sink http://www.ohwr.org/attachments/3303/250M_top.jpg
-----Original Message----- From: ARTIQ [mailto:artiq-boun...@lists.m-labs.hk] On Behalf Of Robert Jördens Sent: Wednesday, March 30, 2016 10:08 PM To: artiq@lists.m-labs.hk Subject: [ARTIQ] Fwd: FW: initial specification of the project On Wed, Mar 30, 2016 at 9:53 PM, Grzegorz Kasprowicz <gkasp...@elka.pw.edu.pl> wrote: > Maybe we should come back to the roots:) What if we use standard FMCs > (LPC) with DAC/ADC channels and RF stuff _on_ them. > JESD204B and some pins would go to the FPGA while DAC and RF clock would be > fed externally. > In this way we leave general purpose AMC board and define its > functionality by FMC boards If we make 3 flavours of FMCs: ADC+ADC, > ADC+DAC,DAC+DAC, we would cover several use cases: > Quad ADC, quad DAC, 1xADC 3xDAC, 3xADC 1xDAC. > FMCs with only DAC and RF stuff on it can be simple, 4 layer boards with > external sield. > Look at this shield (my project) > http://www.ohwr.org/projects/fmc-adc-130m-16b-4cha/wiki > In this way we could use existing AFCK for quick tests I was about to suggest that we consider doing that as well. In the end the DAC/ADC can be on the mezzanine. It doesn't matter much in terms of cost. It makes shielding much easier and much more efficient, gets rid of all coax board-to-board connectors (which saves a lot of space again), allows testing on other carrier platforms, allows usage of other mezzanines. The only downside is that a standard FMC does not have much space. But maybe that's fine. Robert. _______________________________________________ ARTIQ mailing list https://ssl.serverraum.org/lists/listinfo/artiq _______________________________________________ ARTIQ mailing list https://ssl.serverraum.org/lists/listinfo/artiq
