Patent ID: 7260757

Claim:
A method for testing first and second sets of electronic devices on a microchip, the first set of devices receiving input data and then sending output data to a first MISR, the second set of devices receiving input data and then sending output data to a second MISR, the method comprising: determining a first seed signature value associated with the first MISR that induces the first MISR to have a first final signature value comprising a plurality of identical binary values when the first set of devices send valid output data to the first MISR when receiving a first predetermined sequence of input data; determining a second seed signature value associated with the second MISR that induces the second MISR to have a second final signature value comprising a plurality of identical binary values when the second set of devices send valid output data to the second MISR when receiving a second predetermined sequence of input data; initializing first and second states of the first MISR and the second MISR, respectively, to the first and second signature values, respectively; inputting the first and second predetermined sequences of input data to the first and second set of devices, respectively, and generating first and second final signatures values from output data received from the first and second set of devices, respectively; and, indicating that the first and second set of devices have failed testing when at least one of the plurality of binary values in the first and second final signature values are not identical.