On-chip analog signal generation for mixed-signal built-in self-test

A new method for generating analog signals with very low complexity and hardware requirements has recently been introduced. It consists of periodically reproducing short optimized bitstreams recorded from the output of a sigma-delta modulator. In this paper, various types of signals generated using the bitstream approach are discussed. Two different silicon implementations are presented, and their performance is analyzed through experimental results. Various ways in which the generators can be used are also demonstrated. Emphasis is placed on the simplicity of the design process and its compact implementation, which are crucial considerations when implementing a built-in self-test strategy.