He started Thinker*Tinker — the YouTube channel where viewers can “examine circuits, play with their equations, and make designs work.” Reference. Phil Rogers. Design low-duty-cycle timer circuits.

[R-B] designed a 555 timer circuit to scan a keypad. Keypads are common interfaces for small projects and require row and column scanning by a microcontroller. [R-B’s] setup allows you to red… ...

Designing astable circuits using the industry-standard 555 timer is a straightforward process when duty cycles are 50% or greater. However, you must overcome the many pitfalls of low-duty-cycle ...