Melody generator schematic

Posted on Jun 3, 2012

This tiny circuit comprising of a single 3 terminal IC UM66 can be built small enough to be placed inside a greeting card and operated off a single 3V flat button cell. There is not much to the circuit. The UM66 is connected to its supply and its output fed to a transistor for amplification. You can either use a 4ohm speaker or a ` flat` piezoelectric tweeter like the one found in alarm wrist watches. If you use the piezo, then it can be connected directly between the output pin 1 and ground pin 3 without the transistor.

Melody generator schematic
Click here to download the full size of the above Circuit.

The UM66 looks like a transistor with 3 terminals. It is a complete miniature tone generator with a ROM of 64 notes, oscillator and a preamplifier. When it first came into market, it was programmed for the "Jingle bells" tune. Now they come with a wide variety of different tunes.

Leave Comment

characters left:

New Circuits



Popular Circuits

model train detector using photocell
Serial to Parallel circuit Shifting Out with 74HC595
Head light timer circuit
hobby power supply circuit
89c51 ds1820 based digital thermometer
obstruction detector with 12c508 ir
Evaluation Board For Single Supply 12-bit 500 Ksps Adc
A Power Management Interface Circuit For Telecom Hot Swap With Local Dc/dc Conve
MC33374 high power voltage switching regulator
Fuzzy Urn
Low Cost Battery Condition Indicator
Chloroplast type 1 SE