<div dir="auto">I've had an SSI2164 running at a fairly low supply voltage, certainly within pedal ballpark voltages.<div dir="auto"><br></div><div dir="auto">Rutger </div></div><br><div class="gmail_quote"><div dir="ltr">Op wo 13 jun. 2018 12:06 schreef Tom Wiltshire <<a href="mailto:tom@electricdruid.net">tom@electricdruid.net</a>>:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Generally speaking I’d be of exactly the same mind, David, but in this case this is a pedal project, so it’s a 9V single supply, which is pretty borderline for a 2164. Or pretty much any other obvious VCA chip except the LM13700, to be honest. The LM13700 is out because the chances of it *not* thumping with a choppy square wave modulation signal like I’m using are going to be minimal. Happy to be proved wrong if anyone knows a way though.<br>
<br>
I could generate a bipolar supply I suppose, but then that requires another chip and makes things more complicated again.<br>
<br>
Tom<br>
<br>
==================<br>
Electric Druid<br>
Synth & Stompbox DIY<br>
==================<br>
<br>
> On 13 Jun 2018, at 04:22, David G Dixon <<a href="mailto:dixon@mail.ubc.ca" target="_blank" rel="noreferrer">dixon@mail.ubc.ca</a>> wrote:<br>
> <br>
> This sounds like a job for (is it a bird, is it a plane) 2164!!! <br>
> <br>
>> -----Original Message-----<br>
>> From: Synth-diy [mailto:<a href="mailto:synth-diy-bounces@synth-diy.org" target="_blank" rel="noreferrer">synth-diy-bounces@synth-diy.org</a>] On <br>
>> Behalf Of Tom Wiltshire<br>
>> Sent: Tuesday, June 12, 2018 10:33 AM<br>
>> To: synth-diy@synth-diy org<br>
>> Subject: [sdiy] Using DG-series analog switches for PWM VCA<br>
>> <br>
>> I've been working on and off on a "stutter pedal" design. <br>
>> This is basically a severe volume-chopping tremolo effect. <br>
>> I've experimented with using FETs to do the signal muting, <br>
>> but wasn't happy with it. So I thought I'd try a PWM VCA, <br>
>> since I'm controlling the mute signals from a micro <br>
>> controller anyway - unlike the FET mute, I'd actually get <br>
>> some control of the volume level.<br>
>> <br>
>> The chip I decided upon was the DSG413LE:<br>
>> <br>
>> <a href="http://www.farnell.com/datasheets/2311996.pdf" rel="noreferrer noreferrer" target="_blank">http://www.farnell.com/datasheets/2311996.pdf</a><br>
>> <br>
>> Since the PWM needs to be at a reasonable frequency, I'm <br>
>> unlikely to have massive control over the gain (9-bit PWM at <br>
>> 62.5KHz would give me -54dB attenuation before 'Off"). But <br>
>> since the alternative was a FET that was basically "on" or <br>
>> "off" this still represents an improvement!<br>
>> <br>
>> Has anyone else done anything like this? Do you have any <br>
>> experience to share or gotchas that I should avoid? How do <br>
>> the DG-series chips compare with the old 4066 circuits that <br>
>> I've seen this technique used with?<br>
>> <br>
>> Thanks,<br>
>> Tom<br>
>> <br>
>> <br>
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>> <br>
> <br>
<br>
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</blockquote></div>