An on-chip multi-channelwaveform monitor for mixed-signal VLSI diagnostics

Abstract

On-chip multi-channel waveform monitoring technique enhances built-in test and diagnostic capability of mixed-signal VLSI circuits. An 8-channel prototype system incorporates adaptive sample time generation with a 10-bit variable step delay generator and digitization with a 10-bit incremental reference voltage generator. The prototype in a 0.18-/spl mu/m CMOS technology demonstrated on-chip waveform acquisition at 40-ps and 200-/spl mu/V resolutions. The waveforms were as accurate as those acquired by an off-chip measurement technique, while 95% reduction of measurement time was achieved.