You may either use a piezo tweeter or an 8-ohm, 500mW speaker at the output. This simple electronic doorbell has not been tested. During the standby period, the IC consumes nominal current of a few ...

Ever hear of a piezo-optomechanical circuit? We hadn’t either. Let’s break it down. Piezo implies some transducer that converts motion to and from energy. Opto implies light.

A piezo tweeter has an impedance (this is a posh word for resistance for our purposes) of something like five kiloohms. The 30 ohm resistor would increase this to 5,030 ohms.

While Murata’s super tweeter is not able to directly reproduce low bass or midrange frequencies, it is able to reproduce the higher-order harmonics of these lower frequencies.