This circuit was found in an Elektor from the 90s. The integrated circuits are not very common today.
This charger makes use of the LTC4026. We found it in a 2005 Linear Technology publication. The circuit...
This circuit uses a 4020 counter that divides the frequency up to 210, being found in a former...
This version of the traditional debounce circuit was found in a 1964 documentation. The circuit...