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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText>You are right Tom..<o:p></o:p></p><p class=MsoPlainText><span lang=EN-CA>I'm looking now for at least 14bits ADC.. 16 bits will probably be.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>12 bits DAC's should be fine.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Maxim MX7705EPE+ 16 bits ADC could do (I think).<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA>As a note here:<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>I saw that synthesizers.com has a quantizer module Q171<br>that uses ADC/DAC process on incoming CV’s.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Here are the specs:<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><u><span lang=EN-CA style='font-size:12.0pt'>Specifications:<o:p></o:p></span></u></p><p class=MsoPlainText><span lang=EN-CA style='font-size:12.0pt'>Panel Size: Single width 2.125"w x 8.75"h.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA style='font-size:12.0pt'>Quantization Method: Processor controlled ADC/DAC.<o:p></o:p></span></p><p class=MsoPlainText><b><span lang=EN-CA style='font-size:12.0pt'>ADC Inputs: 10-bit with precision buffer/scaler.<o:p></o:p></span></b></p><p class=MsoPlainText><b><span lang=EN-CA style='font-size:12.0pt'>DAC Outputs: 12-bit with precision buffer/scaler.<o:p></o:p></span></b></p><p class=MsoPlainText><span lang=EN-CA style='font-size:12.0pt'>Gate Inputs: 0-5V minimum, rising edge.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA style='font-size:12.0pt'>Gate Outputs: 0-5V, 5ms on, 2ms minimum off.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA style='font-size:12.0pt'>Power: +15V@30ma, -15V@30ma, +5V@50ma.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><a href="https://www.synthesizers.com/products/q171/q171data.pdf">https://www.synthesizers.com/products/q171/q171data.pdf</a><o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><br>The CV inputs are fed to precision opamps OPA4277<br>then routed to a micro MEGA644P’s internal 10 bits ADC.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>The CV outputs are from 12bits DAC’s LTC1448.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><br>So… I’ve not tried this module but assumes it works correctly<br>using a micro’s internal 10bits ADC and an external 12bits DAC.. ??<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Hmmm.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=FR style='mso-fareast-language:FR-CA'>-----Message d'origine-----<br>De : Tom Wiltshire [mailto:tom@electricdruid.net] <br>Envoyé : 29 janvier 2021 15:37<br>À : Jean-Pierre Desrochers<br>Cc : SYNTH DIY<br>Objet : Re: [sdiy] CV/Gate delay project..</span></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I think you’ve answered your own question:<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>> around 10 steps between each semi-tone.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>That’s 10 cents, clearly audible. E.g. Not good enough.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Tom<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>==================<o:p></o:p></p><p class=MsoPlainText> Electric Druid<o:p></o:p></p><p class=MsoPlainText>Synth & Stompbox DIY<o:p></o:p></p><p class=MsoPlainText>==================<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>> On 29 Jan 2021, at 16:28, Jean-Pierre Desrochers <<a href="mailto:jpdesroc@oricom.ca"><span style='color:windowtext;text-decoration:none'>jpdesroc@oricom.ca</span></a>> wrote:<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> Hi list,<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> I'm working on a new module for my DOTCOM modular.<o:p></o:p></p><p class=MsoPlainText>> It would memorize incoming CV's and Gate's state for 2msec up to 10sec <o:p></o:p></p><p class=MsoPlainText>> then spit the stream in steps of 1msec.<o:p></o:p></p><p class=MsoPlainText>> The code for Gate memorizing is done.<o:p></o:p></p><p class=MsoPlainText>> I'm now wondering if using a Microchip PIC 10bits ADC is linear enough <o:p></o:p></p><p class=MsoPlainText>> to read incoming CV values (0 to 8vdc)...<o:p></o:p></p><p class=MsoPlainText>> There will be an input buffer amplifier that will take care of taking <o:p></o:p></p><p class=MsoPlainText>> down the 0to8vdc to 0to5vdc for the PIC.<o:p></o:p></p><p class=MsoPlainText>> Incoming CV's 0-8vdc, 12 semitones/octaves.. that makes 1024 / (8 x 12)..<o:p></o:p></p><p class=MsoPlainText>> around 10 steps between each semi-tones.<o:p></o:p></p><p class=MsoPlainText>> My worry is the PIC ADC linearity precision..<o:p></o:p></p><p class=MsoPlainText>> The 10bits memorized values will be output using a 12bits SPI DAC.<o:p></o:p></p><p class=MsoPlainText>> I have a bunch of old PIC16F88 that I want to utilize here.<o:p></o:p></p><p class=MsoPlainText>> Old but still usable for SPI.<o:p></o:p></p><p class=MsoPlainText>> What do you think about PIC's ADC linearity wise ?<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> JP<o:p></o:p></p><p class=MsoPlainText>> <o:p></o:p></p><p class=MsoPlainText>> _______________________________________________<o:p></o:p></p><p class=MsoPlainText>> Synth-diy mailing list<o:p></o:p></p><p class=MsoPlainText>> <a href="mailto:Synth-diy@synth-diy.org"><span style='color:windowtext;text-decoration:none'>Synth-diy@synth-diy.org</span></a><o:p></o:p></p><p class=MsoPlainText>> <a href="http://synth-diy.org/mailman/listinfo/synth-diy"><span style='color:windowtext;text-decoration:none'>http://synth-diy.org/mailman/listinfo/synth-diy</span></a><o:p></o:p></p><p class=MsoPlainText>> Selling or trading? Use <a href="mailto:marketplace@synth-diy.org"><span style='color:windowtext;text-decoration:none'>marketplace@synth-diy.org</span></a><o:p></o:p></p></div></body></html>