I need to calculate the stress parameter (rated specification value, actual stress parameter and derating in %) for my circuit. i have calculated for the resistors, capacitors etc.
how to calculate the stress parameter for these ic's? (Micro controller, adc's , dac's opto couplers, max232 and other ic's.)
what factors i need to consider?
Generally you do not need to derate IC's, instead you need to derate certain output functions like driver current for PWM IC's or input voltage. deratation is done to improve reliability, and this achieved by operating devices at operating conditions less than rated values.
Hope this helps.
In my experience every customer has a somewhat different set
of deratings. I see 30, 40, 50% current derating depending on
who I talk to. 20 to 50C temperature derating. It's a cost and
risk tradeoff (cost including performance). If you have no data
for physics-of-failure then one wild-a$$ guess may be as good
as another.