Cosel is one of the world's leading power supply manufacturers offering
high-quality, ultra small size AC-DC power supplies,
DC-DC converters of the state-of-the-art technologies, and effective and
easy-to-use noise filters.

Frequently Asked Questions

Q. What is MTBF?

MTBF, which is the abbreviated name for "Mean Time Between Failures", is generally used as a barometer of failure rate of power supply. It is the mean time between failures of a system (excluding repair time).
Failure rate:	λ is constant, i.e. the reliability in the constant failure rate period is represented by exponential distribution.
	R(t) = e^-λt
At this time, MTBF is the reciprocal of the failure rate.
	MTBF = 1 / λ
We calculate MTBF by the part count reliability prediction instituted by EIAJ(Electronic Industries Association of Japan). This standard complying with the part count reliability prediction of MIL-HDBK-217D provides failure rate data for many electronic components.
	EIAJ standard No. RCR-9102

Cosel is one of the world's leading power supply manufacturers offeringhigh-quality, ultra small size AC-DC power supplies,DC-DC converters of the state-of-the-art technologies, and effective andeasy-to-use noise filters.