5 Melody generator circuits using UM66T

In the circuit basically usability base IC UM66T use the sound of music sweet-sounding origin and be usable easily. It uses just integrated one circuit and a loudspeaker, piezo buzzer , the small-sized, and have power supply 3V only. The detail is other of integrated number this circuit.

The Basic UM66Txx Circuit Diagram

The UM66T series are CMOS LSI designed for using in the doorbell, telephone and toy

It is an on-chip ROM programmed for musical performance. They are produced by CMOS
technology, the device results in very low power consumption. Since the UTC UM66TXXL Melody generator IC series include oscillation circuits a compact melody module can be constructed with only a few additional components.

The Basic UM66Txx Circuit Diagram

Part number Song name
UM66T-01L Jingle Bells + Santa Claus Is Coming To Town + We Wish You A Merry
UM66T-05L Home Sweet Home
UM66T-09L Wedding March (Mendelssohn)
UM66T-19L For Alice
UM66T-32L Coo Coo Waltz
UM66T-68L It Is A Small World

Simple music sound using UM66T

Simple music sound using UM66T

Most circuits, we find that the IC number UM66T common because the smaller ICI power consumption of culture is not very easy. Choose music that has many songs together.

Operation of the circuit

When the power supply circuit is currents flowing through LED1 LED1 light and the electricity flowing into pin 2 of IC1 IC1 make music production work.

Not: C1, can change to 10uF or 1uF to more. R2, can change to 100 ohms and lower.

You can hear the normal level of music from 8 ohms speaker. as below video:

The output from pin 3 to C1 through the bias of the legs B Q1 Q1, which will force the amplifier to drive speakers then.

Easy Create Melody Music using UM66T

Easy Create Melody Music using UM66T

Operation of the circuit

When entering the power supply to the circuit. The current flowing through R1 and LED1 LED1 light of the C1 will serve to filter noise ground.

The voltage drop across LED1  to power voltage to signal generator IC1. Then it out of three legs to the amplifier. They are Q1, Q2 connected together in a Darlington transistor.

In order to drive speakers with R1, R2 in Limited current circuit will flow through each device to prevent equipment damage.


You can hear melody music sound for this circuit at below.

Musical doorbell Buzzer Sound using UM66T

This is a simple musical doorbell sound or Buzzer sound circuit. When I switch to musical voice out of small speakers, a period of time. This size range of power supply 3V.

The UM66T is audio production functions of various Toy Gallery.

And we add a time delay circuit with includes a transistor and a capacitor.

Musical doorbell Buzzer Sound using UM66T

Operation of the circuit

When the switch S1 is pressed. Then, capacitor C1 will charge as fast as a result, Q1, Q2 the bias. It causes the voltage drops across R3. Next, there is a current flowing into pin 2 of IC1. So, it causes IC1 to work. If the switch S1 C1 will be discharged, through R1 to Q1.As a result, the lighter music of the period ever releases the audio when the switch is based on the value of C1.

Touch sensitive musical bell using UM66T

This is a Touch-sensitive musical bell circuit. It is fun, interesting. Then, we can create the music enjoy listen to the touch of a button to control metal.

When our hands touch point. Then, the Circuit will produce a musical sound with UM66T-IC1 out to piezo speaker immediately.

This circuit uses a very little amount. It is suitable for beginners, or parents and children together to build this project. To increas the Electronics experience as well.

Operation of the circuit. In the normal range will not work Piezo Tweeter speakers on tap, but not the point of A Q1 Q2 will flow and the work of the bias voltage falls across R2.

Touch sensitive to the melody alarm using UM66t

And the current flowing into pin 2 of IC1 IC1 make music production work out of three legs with Piezo speakers act as signals to change the music

The parts list of this circuit
You would want your children to play together. Let’s see the list of devices. To convenience in order at electronic components shop.

1. IC1_UM66TXX See a list of songs here.
2. Q1_2N3904_45V 0.1A NPN Transistor
3. Q2_2N3906_45V 0.1A PNP Transistor

0.25W 5% Resistors
4. R1_100K
5. R2_10K
6. R3_100Ω
7. C1_10uF 25V_Electrolytic Capacitors
8. PZ1_Peizo speaker
9. B1_1.5V x 2 battery

The circuit concept

This circuit or projects have too much useful. Addition to building a play Just look around. It can also be converted to a warning or reminder. When we touch a doorknob, sounding music up.

or Adapted to strap style on the knob. When we stay in hotels We do not trust it. This is very convenient and safe. Reminds us to know first. Who unwanted entering our rooms.

How to build

This project is not used in many components. So, we can assemble on the universal PCB board. The wiring for circuit wiring and various components. You can view the example in Video below.

For the polarity of the electrolytic capacitors Pin of the IC is not an error.

This project works!

How to increase music loud up!

The circuit above the music of UM66T is very weak. My son wants to hear music loud up. I think the piezo speaker is very small. We should use a normal speaker better it.

So, I remove piezo and replace with a few components as Figure 2.

We use BC549 or 2N3904 -transistor amplifier converts a small signal of IC1 into a larger signal at the speaker 8 ohms, 2 inches.

And Resistor-1K for limit current to its base.

Figure 2 The increasing music loud up by transistor.

He is very happy with this his job.

This Post Has 4 Comments

  1. easy create music by UM66 IS NOT WORKING

  2. Hi, himanshu banti

    Thanks for your comment.
    Now, This circuit works please see in text.

  3. very good poroject , but i want one touch to continue alarm

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