Switching supply test mode for analog cores

摘要

An integrated circuit such as an application specific integrated circuit (ASIC) which has operational power supplies provided for different respective analog cores and digital logic and/or macros may be tested using on-chip power supplies, preferably comprising operational amplifiers connected as voltage followers and controlled by a band-gap voltage source or a voltage divider, drawing power from a single power supply to the chip which is generally provided in a standardized pin-out location. Disablement of respective operational amplifiers also provides electrical isolation of the respective cores during testing. A reduced pin-count is involved in the testing procedure since operational power supply connections can be open circuited or "tri-stated". On-chip power supplies for testing provides power while avoiding a need to provide low-noise power supplies and/or complex switching in a test system or to utilize custom front-end boards or both to provide power to arbitrary chip or package connections.