The design change decreased the required 9 external pins to 8, so the IC could be fit in an 8-pin package instead of a 14-pin package. After this design was tested and found to be without errors, Camenzind got the idea of using a direct resistance instead of a constant current source, finding that it worked satisfactorily. The first design for the 555 was reviewed in the summer of 1971. Camenzind's idea was originally rejected, since other engineers argued the product could be built from existing parts sold by the company however, the marketing manager approved the idea.
Camenzind proposed the development of a universal circuit based on the oscillator for PLLs and asked that he develop it alone, borrowing equipment from Signetics instead of having his pay cut in half. Signetics subsequently laid off half of its employees due to the 1970 recession, and development on the PLL was thus frozen. He designed an oscillator for PLLs such that the frequency did not depend on the power supply voltage or temperature. In 1968, he was hired by Signetics to develop a phase-locked loop (PLL) IC.
The timer IC was designed in 1971 by Hans Camenzind under contract to Signetics.
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