DSP Hotline Techbits : Time Between Failure

Mean Time Between Failure (MTBF), Failure in Time (FIT), or Failure Rate for TMS320C40

MTBF or failure rate is not readily available for TI DSP devices. These reliability parameters are not specified and TI does not maintain or support any reliability prediction methodologies. TI provides any life test data that has been collected. TI periodically runs accelerated life tests and other environmental tests for qualification purposes or to monitor the observed reliability characteristics of TI DSP devices. Through this reliability monitoring program, representative devices are selected from each product family for testing. A customer can take our accelerated test data and project a failure rate in his use environment.

During device qualification of the C40 device 129 units completed 1000 hours of 140C/6.5 volt life test with three failures. An acceleration factor is calculated for these tests assuming a 0.5 eV activation energy. Using this acceleration factor one can extrapolate to an assumed 55 C use condition:

55.00 Failure Rate Temperature in degrees C (Assumed operating temp)
140.00 Stress Temperature in degrees C <=== Accelerated Test temperature.
0.50 Activation Energy (eV)
60 Desired Upper Confidence Level (UCL)
1000 Hours on Test
129 Quantity Tested
3 Number of Failures
38.120 Acceleration Factor

Gives an observed failure rate based upon accelerated testing of 849 Fit (Fit = failures per billion hours)

Following this test probe stress conditions were implemented to reduce/eliminate the early failures which were observed during this test.

Mean Time Between Failure (MTBF), Failure in Time (FIT), or Failure Rate for TMS320C44

During device qualification of the C44 device 123 units completed 600 hours of 140C/6.5 volt life test with zero failures. An acceleration factor is calculated for these tests assuming a 0.5 eV activation energy. Using this acceleration factor one can extrapolate to an assumed 55 C use condition:

55.00 Failure Rate Temperature in degrees C (Assumed operating temp)
140.00 Stress Temperature in degrees C (Test temperature.)
0.50 Activation Energy (Ev)
60 Desired Upper Confidence Level (UCL)
600 Hours on Test
360 Quantity Tested
0 Number of Failures
38.120 Acceleration Factor

Gives an observed failure rate based upon accelerated testing of 328 Fit (Fit = failures per billion hours)

Quality and Reliability Data Disclaimer:

Quality and reliability data provided by Texas Instruments is intended to be an estimate of product performance based upon history only. It does not imply that any performance levels reflected in such data can be met if the product is operated outside the conditions expressly stated in the latest published data sheet for a device.

Use Disclaimer:

Plastic encapsulated TI semiconductor devices are not designed and are not warranted to be suitable for use in some military applications and/or military environments. Use of plastic encapsulated TI semiconductor devices in military applications and/or military environments, in lieu of hermetically sealed ceramic devices, is understood to be fully at the risk of the buyer.