May 17, At Speed Production Testing of USB Mb/s Transceivers Dave Thompson Lucent Technologies

May 17, Outline w Signal Characteristics w Characterization & Production Tests w Test System Capabilities w Special Test modes & hardware w Summary

May 17, Signal Characteristics w Very low differential signal swings – mV w High speed serial data rate – 480Mb/s w Speed signaling – Detection of FS; LS; HS(CHIRP) w Other Challenges – Jitter; Termination; Suspend/resume

May 17, USB2.0 HS Signal Example 480Mb/sec At-Speed Package Test

May 17, Characterization Tests w Jitter testing w At speed signal integrity w Rise/fall time measurements w Suspend current measurement w Dynamic current measurement w Squelch level measurement

May 17, Characterization Test: USB2.0 Data Eye

May 17, Typical Production Tests w Fault coverage testing w At speed functional testing w DC parametric testing w Speed detection testing w Suspend/resume testing w IDDQ testing

May 17, Test System Capabilities w Test system concerns: – Generate accurate waveforms < 800mV – Accurately receive signals < 800mV – Measure the “z” state – 480Mb/s data rates – Detection of FS; LS; HS(CHIRP) – Jitter; Termination; Suspend/resume u HP F330 jitter test not adequate

May 17, Special Test: Modes & Hardware w Several on-chip test modes – IDDQ – PLL bypass – Suspend/Resume test mode – DFT reduces USB2 test complexities u For example, speed signaling

May 17, Special Test: PLL Bypass Mode

May 17, Special Test: Modes & Hardware w Utilize an HP F330 w Test system modifications: – Used paired drivers/comparators – Implemented fly-by; vt-divider – 4X mode for 400MB/s(Joergware)

May 17, Special Test: Clock/Data Recovery

May 17, Test Complexity Comparison: USB2.0 & 1394 Test Type EasierSameHarder At-Speed-BypassX At-Speed-Non Bypass X DC Parametric X Suspend/ResumeX IDDQX

May 17, At Speed Production Testing of USB Mb/s Transceivers w Standard Digital Test System w Custom Daughter Card not Required w Typical production test equipment can test 480Mb/s components, for example: – Lucent’s USB2 Transceiver Test Chip Summary