it harder for the test to detect. However, Iddq is so useful that designers are taking steps to keep it working. One particular technique that helps is power gating, where the entire power supply to each block can be switched off using a low leakage switch. This allows each block to be tested individually or in combination, which makes the tests much easier when compared to testing the whole chip. References Further reading (NB. This is a summary of the basic ideas behind Iddq testing, the history of the technique, and many of its characteristics.) Available Iddq technology Integrated circuits