16-channel single-chip current-mode track-and-hold acquisition system with 100 DB dynamic range

Testing of mixed-mode VLSI systems demands specialized instrumentation tools to simultaneously source and track multiple analog and digital signals. We present a single-chip solution for synchronous acquisition of 16 channels of independent currents, ranging five orders of magnitude in dynamic range over four scales. The digitally programmable chip is one component in an integrated system that we developed with 64 analog and 64 digital I/O channels, for timed instrumentation of micropower VLSI systems covering subthreshold and above threshold MOS regions of operation. We present circuits implementing the programmable current amplification, log-domain anti-alias filtering, and integrating differential current-to-voltage acquisition, and include experimental results from the 16-channel prototype fabricated through MOSIS in a 1.2 mu m CMOS process.