•  
  •  

Melody generator for greeting cards

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.
 
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.

If there are any problems please contact webmaster@electronic-circuits-diagrams.com

Please share & like

MITSUBISHI MR-C10A1-UE (LC1A18) AC MOTOR SERVO DRIVE CONTROLLER AMPLIFIER. NEW
$198.0 MITSUBISHI MR-C10A1-UE (LC1A18) AC MOTOR SERVO DRIVE CONTROLLER AMPLIFIER. NEW picture
New HBM 1-AE301 amplifier clip
$395.0 New HBM 1-AE301 amplifier clip picture
VISOLUX 10-30VDC KSU-LL-IR-1237/46 AMPLIFIER. PEPPERL & FUCHS. NEW
$89.95 VISOLUX 10-30VDC KSU-LL-IR-1237/46 AMPLIFIER. PEPPERL & FUCHS.  NEW picture
3 pc NEW OMRON M2BJ-B24-D
$180.0 3 pc NEW OMRON M2BJ-B24-D picture
STM V9/S77-BP-19 AMPLIFIER MICRO SENSOR V9S77BP19, P/N: 1380001 NEW
$14.95 STM V9/S77-BP-19 AMPLIFIER MICRO SENSOR V9S77BP19, P/N: 1380001 NEW picture