Low battery indicator 555 (CB9551E)

This circuit can operate with different voltages, depending on the zener used. We found it in a 90s American documentation.

Two outputs DC to DC converter (CB7531E)
This circuit was obtained in Linear Technology documentation from 1993. The circuit provides 3.3 V and...
Pulse Extender (CB1444E)
This circuit is from the National Semiconductor CMOS manual of 1977. What this circuit does is to...
Repellent with 555 IC (CB24933E)
This circuit operates from 25 to 65 kHz depending on the transducer used and the settings. We...