Testing the operation of integrated circuits by simulating a switching-mode of their power supply inputs

Apparatus for testing the operation of an integrated circuit (IC) while maintaining a supply input to said IC constantly active during a test, comprising:

• circuitry for generating a logic indication signal, said indication signal providing a first logic level indicating an active state of said supply input and a second logic level indicating an inactive state of said supply input;
• circuitry for simulating the inactive state of said supply input by processing said first logic level and by generating a third logic level that is at least substantially similar to said second logic level;
• means for applying said third logic level to one or more of at least one signal-carrying contact within said IC;
• and
• means for accessing one or more of said at least one signal-carrying contact within said IC and reading one or more corresponding signal values responsive to said applied third logic level.

A method, comprising:

• supplying an input voltage signal to an integrated circuit;
• and
• testing at least a portion of the integrated circuit using an indication signal, the indication signal comprising a first logic level representing an active state of the input voltage signal and a second logic level representing an inactive state of the input voltage signal;
• wherein the input voltage signal remains at the active state during the testing.

An integrated circuit, comprising:

• an input operable to receive an input voltage signal;
• and
• circuitry operable to receive an indication signal and generate one or more values during a test of the integrated circuit, the indication signal comprising a first logic level representing an active state of the input voltage signal and a second logic level representing an inactive state of the input voltage signal;
• wherein the input voltage signal remains at the active state during the test.