scan path

1 definition found

scan path - Free On-line Dictionary of Computing (26 May 2007) :

  scan path
  
     (circuit design) A technique used to increase the
     controllability and observability of a logic circuit by
     incorporating "scan registers" into the circuit.  Normally
     these act like flip-flops but they can be switched into a
     "test" mode where they all become one long shift register.
     This allows data to be clocked serially through all the scan
     registers and out of an output pin at the same time as new
     data is clocked in from an input pin.
  
     Using this technique, the state of certain points in the
     circuit can be examined and modified at any time by suspending
     normal operation and switching to test mode.  If the scan path
     is placed adjacent to the circuit's input and output pins then
     this is known as "boundary scan".
  
     (1995-02-14)