ISO7641FC: Equation of the average lifetime

Hi Kuramochi-san,

We do not have any equation for the average lifetime of ISO7641FC. The lifetime plot that we provide is generating from the lifetime test called Time Dependent Dielectric Breakdown (TDDB) which is a standard test practiced in the industry to find out device's lifetime.

The basic test methodology is to apply a stress voltage from the input to the output of the DUT in a two-terminal configuration using a high-voltage source, while maintaining the still-air, ambient-air temperature at 150°C. The start of the test activates a timer; this timer is stopped when the current in the circuit exceeds a particular fail current level (like 100uA), which meant that the dielectric had failed. The time taken by device is noted for each applied test voltage. DUTs were tested independently of each other (one DUT per test) at each test voltage to get statistically valid results. Sufficient number of devices are tested at multiple test voltages to get the most practical device lifetime curve.

I hope this answers your question, thank you.


Regards,
Koteshwar Rao