This interesting circuit for the RDA8851 allows you to obtain two volumes with a simple touch. The circuit is from an Electronics Now from December 1988. Note the amplifier voltages.
Another of the many tachometer circuits we have on our site. This one is from the September 1976...
More and more supercapacitors are being used as supplementary sources of energy in several...
We find this circuit in a 555 application manual. The circuit generates triangular signals that...