Hello,
I would like to interface an external FPGA (on an eval board) to the DC2365A-B LTC2357-18. Is this possible? Is there documentation describing how this can be done?
Thanks!
Mike
LTC2357-18
Production
The LTC2357-18 is an 18-bit, low noise 4-channel simultaneous sampling successive approximation register (SAR) ADC with buffered differential, wide common...
Datasheet
LTC2357-18 on Analog.com
Hello,
I would like to interface an external FPGA (on an eval board) to the DC2365A-B LTC2357-18. Is this possible? Is there documentation describing how this can be done?
Thanks!
Mike
Hi Mike,
Yes, you can connect an external FPGA board to the DC2365A. There is no existing documentation for this but it should be a straightforward process. Tie node WRIN low. Tie node WRIN2 high (high is the default for this node). Remove R47 and R52.
Connect CNV, SDOx, SCKI, SDI and if necessary SCKO and BUSY between the two boards, using shielded, series terminated cables. Note that the DC2365A is labeled with LTC2358 pin names. LTC2357 pin numbers and names do not match LTC2358 for SDOx. The clock will come from the FPGA board at this point, not J1.
Connect the ground planes of the two boards together with solder wick or copper tape to make a good low inductance connection.
Make sure that the DC2365A and the FPGA board are using the same I/O voltage. By default the DC2365A is set to 2.5V but it can be set to 3.3V with JP2.
That should be all that is required.