Challenges of built-in current sensor designs

Built-in current sensors (BICSs) are very useful for both off-line and on-line testing. However, the practical use of BICS remains illusive due to several major concerns. This paper addresses the trade-off in design considerations and with examples from the existing designs. We then present a new BICS design which we believe can be easily incorporated into design automation process. Assuming that the CUT has been equipped with a voltage regulator, the proposed BICS obtains the I _DDQ sample from the voltage regulator directly and non-destructively. The insertion of the proposed BICS can be easily automated due to its simplicity