Logic built-in self-test (or LBIST) is a form of
built-in self-test
A built-in self-test (BIST) or built-in test (BIT) is a mechanism that permits a machine to test itself. Engineers design BISTs to meet requirements such as:
*high reliability
*lower repair cycle times
or constraints such as:
*limited techn ...
(BIST) in which hardware and/or software is built into
integrated circuit
An integrated circuit (IC), also known as a microchip or simply chip, is a set of electronic circuits, consisting of various electronic components (such as transistors, resistors, and capacitors) and their interconnections. These components a ...
s allowing them to test their own operation, as opposed to reliance on external
automated test equipment.
Advantages
The main advantage of LBIST is the ability to test internal circuits having no direct connections to external pins, and thus unreachable by external automated test equipment. Another advantage is the ability to trigger the LBIST of an integrated circuit while running a built-in self test or power-on self test of the finished product.
Disadvantages
LBIST that requires additional circuitry (or
read-only memory
Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing sof ...
) increases the cost of the integrated circuit. LBIST that only requires temporary changes to
programmable logic or
rewritable memory avoids this extra cost, but requires more time to first program in the BIST and then to remove it and program in the final configuration. Another disadvantage of LBIST is the possibility that the on-chip testing hardware itself can fail; external automated test equipment tests the integrated circuit with known-good test circuitry.
Related technologies
Other, related technologies are
MBIST
A built-in self-test (BIST) or built-in test (BIT) is a mechanism that permits a machine to test itself. Engineers design BISTs to meet requirements such as:
*high reliability
*lower repair cycle times
or constraints such as:
*limited techni ...
(a BIST optimized for testing internal
memory
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembe ...
) and ABIST (either a BIST optimized for testing
arrays
An array is a systematic arrangement of similar objects, usually in rows and columns.
Things called an array include:
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Music
* In twelve-tone and serial composition, the presentation of simultaneous twelve-tone sets such that the ...
or a BIST that is optimized for testing
analog circuitry). The two uses may be distinguished by considering whether the integrated circuit being tested has an internal array or analog functions.
See also
*
Built-in self-test
A built-in self-test (BIST) or built-in test (BIT) is a mechanism that permits a machine to test itself. Engineers design BISTs to meet requirements such as:
*high reliability
*lower repair cycle times
or constraints such as:
*limited techn ...
*
Built-in test equipment
Built-in test equipment (BITE) for avionics primarily refers to passive fault management and diagnosis equipment built into airborne systems to support maintenance processes. Built-in test equipment includes multimeter
A multimeter (also know ...
*
Design for test
Design for testing or design for testability (DFT) consists of integrated circuit design techniques that add testability features to a hardware product design. The added features make it easier to develop and apply manufacturing tests to the desig ...
*
Power-on self-test
A power-on self-test (POST) is a process performed by firmware or software routines immediately after a computer or other digital electronic device is powered on.
POST processes may set the initial state of the device from firmware and detec ...
External links
Built-in Self Test (BIST)*
{{DEFAULTSORT:Logic Built-In Self-Test
Integrated circuits