Cyclone V and some transceiver CDR/PLL parameters

Introduction Connecting an Intel FPGA (Altera) Cyclone V’s Native Transceiver IP to a USB 3.0 channel (which involves a -5000 ppm Spread Spectrum modulation), I got a significant bit error rate and what appeared to be occasional losses of lock. Suspecting that the CDR didn’t catch up with the frequency modulation, I wanted to try [...]

Quartus, timing closure: Obtaining a concise multi-corner timing path report

Introduction The natural thing to do when an FPGA design fails timing is to take a detailed look at the critical paths, based upon a timing report showing the logic elements and their delays of this path. If you’re not a heavy user of Intel’s FPGAs (a.k.a. Altera), it may not be so trivial to [...]