The today's Diotec Semiconductor AG is founded in 1973 in Heitersheim, Germany . From the beginning, the company specializes in the production of diodes and rectifiers and becomes a known brand throughout Europe.

The company expands within Europe and founds in 1989 another facility in Trbovje, Slovenia. In addition to Heitersheim, here is beside others the second chip production of Diotec.

The production facility Diotec Shanghai is founded in 2005. It has the main target to support the Chinese branches of exisiting Diotec customers.

In 2007, the new facility Diotec India starts production. It is located in Pune, near to Mumbai, the "Gateway of India".