This CMOS circuit for LED displays is from a Radio Electronics magazine from February 1989. The circuit has an enable pulse for storing the value shown on the display.
This oscillator with crystal for overtone operation was found in an old American documentation. The coil...
In the figure we have a basic PLL circuit with the LM567 or equivalent. The circuit is from a 1977...
The A3906 integrated circuit from Allegro MicroSystems (www.allegro.com) consists of a single...