Receiver Circuit Testing Test setup Eye diagrams BER measurement Eye BER relationship Evaluation Boards Circuit Test Setup Pattern Generator Attenuator Oscilloscope Signal Monitoring Terminated 50 coax for 1 Mbps capacitance NRZ data 50 ohms 1 2piRC data rate RF Oscillation Prevention Grounded coax for all inputs Single ground point for bias RF Circuit Test 50 transmission line to chip Stripline printed circuit boards or short lines 50 output drivers BER Measurement PRBS source Attenuation Error measurement BER PRBS Atten PRBS source 0 5 0 0 5 20 40 60 80 100 120 140 FDDI code 274213IIJKTT Band Passed FDDI Code Zero Crossing Pseudo random data is severe test of receiver Length of zero or one string is critical ISI Eye diagram is open for low ISI Attenuation Sensitivity of receiver BER over a range of input power Pin and data rates Dynamic range of transimpeadance Amp TIA limits maximum input power May need to reduce Pin to get normal operation Error Measurement 1 10 1 10 Correlate PRBS and output data BER number of errors data bits sent BER 10 9 or 10 11 typical i e 1 error per Gbit of data 10 9 1 10 1 10 1 10 1 10 1 10 1 10 4 5 6 7 8 9 10 11 40 35 30 25 BER is related to Eye Diagram Vertical eye opening Proportional to x in BER 10 x Practically only good to 10 8 MAX 3266 Evaluation Kit Hook your input into J1 and your Limiting Amplifier into J2 and J3 and your ready to test MAX3264 Evaluation Kit Connect your TIA to J4 and J5 and J2 and J3 to your output and your ready to go LOS threshold programming also done here Test of Eval Boards