Open Music Labs Forums

Hi there,

I've been wanting to build my own synthesizer for sometime and I really liked the sound you got out of such a simple 8bit chip. It's really great that MIDIVamp is open hardware, I sympathize with this kind of philosophy. Also, buying was not a good option for me: Brazil has a 60% tax for imported products + local taxes over the product and shipping fees...

I began getting a ATmega328P-PU sample from Atmel, but reading the parts list I saw this entry: "S-1112B30MC (MUST BE THIS ONE)". So I started searching for it at , and the only distributor that has it in stock is Mouser, but it's not worth the shipping fee and taxes (). Is there an alternative IC for this?

Texas Instruments sends free samples of their stuff, so I found similar chips ():
-TLV7163030P
-TLV7163318P
-TPS7A3701

Could someone help me with the voltage regulator choice?
I guess an option would be to get power from another source then the midi port...
Is there a problem in using a 3.3v or 5v power source from my Arduino Due?

Thank you in advance,

Daniel

hello daniel,

that is awesome that you are building your own synth! do you want it to be phantom powered from the midi data line like the original midivampire-1? if you are ok with powering it from a 3v or 5v supply, then you dont need that voltage regulator. you can just power it regularly, and even put a midi compliant opto-coupler on it.

if you want, the whole thing could probably just be done on an arduino as well.

Not sure if this will help you, but I have successfully been using Texas Instruments TLV70030 (http://www.ti.com/lit/ds/symlink/tlv70030.pdf) as a drop-in replacement for the S-1112B30MC in my MIDIvamp-I. Although using a TSOT-23-5 directly on a breadboard might be a bit fiddly. :)

I admire your plan to building your own synth. I've never had enough patience to do it by my own :D