Telephone handset tone dial encoder

  
This encoder uses a single contact per key keyboard and provides all other switching function electronically. The diode between terminals 8 and 15 prevents the output going more than 1 volt negative with respect to the negative supply V-
Telephone handset tone dial encoder - schematic

The circuit operates over the supply voltage range from 3 volts to 15 volts.




Leave Comment

characters left:

New Circuits

.