LM567 IC is a tone decoder chip which is designed basically for recognizing a specified frequency band, and activating the output in response to the detection. Needless to say this chip can be used for a number of different applications, the most common being in the field of remote controls, and security systems.
Extensive settable frequency range (0.01 Hz to 500 kHz), meaning the sensing passband may be set right from 0.1 to 500 kHz, giving an option of a huge range so that unlimited unique configuration can be achieved from this chip.