The DEV-TRON SI-36 calculator was based on a two-chip set of LSI (Large Scale Integration) chips from MOS Technology. Each of the chips is housed in a ceramic package with 28 pins. It’s possible, though unconfirmed, that MOS Technology was the first manufacturer of integrated circuits to pack the logic of a fully functional scientific calculator into just two chips. This chip set was utilized by various calculator manufacturers. MOS Technology’s main customer for calculator chip sets was Commodore, which eventually acquired the company (renaming it Commodore Semiconductor Technology) to produce chips for Commodore calculators.