UM3482 Melody IC

vick5821 · Aug 3, 2012

Hey there, I am connecting this IC according to the right hand side diagram. And it works. But then that connection will just keep repeating the same melody. So, how can I modify it so that I can play all the 12 melodys available in the IC AUTOMATICALLY when the supply in ON? I plan to make a music box that can play the 12 songs automatically.

Thank you

Harald Kapp · Aug 3, 2012

Select playing mode 2 (see datasheet).
Add a timer that triggers CE such that after each song CE has a L-H edge transition. You will have to set the rate of the timer according to the length of the songs.
Use e.g.a 555 timer IC

vick5821 · Aug 3, 2012

Harald Kapp said:

Select playing mode 2 (see datasheet).
Add a timer that triggers CE such that after each song CE has a L-H edge transition. You will have to set the rate of the timer according to the length of the songs.
Use e.g.a 555 timer IC
Click to expand...

I think the time for all the songs are not consistent ><

Harald Kapp · Aug 3, 2012

You could try to detect the end of a song by looking at the AC signal at the speaker - transistor connection. If this signal goes to static HIGH for some time (depending on the intervall between songs) the end of a song has been reached. You can generate an L-H edge to trigger the IC from that intervall by using a low-pass and a Schmit-Trigger.

I'll leave the details to you.

vick5821 · Aug 3, 2012

Harald Kapp said:

You could try to detect the end of a song by looking at the AC signal at the speaker - transistor connection. If this signal goes to static HIGH for some time (depending on the intervall between songs) the end of a song has been reached. You can generate an L-H edge to trigger the IC from that intervall by using a low-pass and a Schmit-Trigger.

I'll leave the details to you.
Click to expand...

How's the algorithm for this ?

Harald Kapp · Aug 3, 2012

No algorithm. Hardware. Look up envelope detector or start here http://en.wikipedia.org/wiki/Envelope_detector
Use a Schmitt Trigger after the envelope detector to generate a CS signal for the music IC

UM3482 Melody IC

vick5821

Harald Kapp Moderator Moderator

vick5821

Harald Kapp Moderator Moderator

vick5821

Harald Kapp Moderator Moderator

A programmable melody generator