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What parameter of electrical specification can the life be estimated?

Last Updated:01/15/2018


The life of a photocoupler is expressed by using current transfer ratio CTR, but CTR is not defined for some products of the high-speed photocoupler (except the analog output type). In this case, by what parameter of the electrical specifications can the life be estimated?


Even the high-speed photocoupler degrades when power is applied. This degradation can be checked by using the threshold input current (IFHL) of the electrical specifications (transfer characteristics).
As the photocoupler degrades, its output no longer changes from high to low, even when a current higher than IFHL defined by the specification flows. By this phenomenon, the life of the photocoupler can be judged as having expired.
For details, contact your nearest distributor.

[Example in Electrical Specifications of PS9117A Data Sheet]
Suitable Products
Photocouplers / Optocouplers