<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">Alfa is usually pretty responsive to direct inquiries. I've bought a whole bunch of their 2164s. <div><br></div><div>At least a year-ish ago, AS3364 was $2.90 @ 100, $1.85 > 1000<br><div><br></div><div>Chris McDowell <br><blockquote type="cite"><div>On Aug 9, 2024, at 11:31 AM, David G Dixon via Synth-diy <synth-diy@synth-diy.org> wrote:</div><br class="Apple-interchange-newline"><div><meta charset="UTF-8"><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024">That sounds great. My only issue is price -- The AS3364 seems to cost about $7 or more, depending on the source, and it does not seem to be possible to buy them directly from Alfa -- at least, I don't see any obvious way to do so from their website.</span></div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024"></span> </div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024">My latest project is going to require about 250 2164 ICs. That's not a problem given what I'm paying for them. Yes, in all but the filter application, the 2164s are all linearized, but I'm paying about 23 cents for TL074s and about 1 cent for 561 caps, so from a cost perspective, it just doesn't make much sense. Linearizing 2164 does add an inch or so to the PCB real estate, but I'm sending the same voltage to a large number (48) of 2164s, so even though they are linearized, only one logarithmic amplifier is needed for all of those 2164s. I do need to buffer those CVs locally, so there is a TL074 sitting next to the 2164, but I would need to do that with the 3364 as well (the datasheet is silent on the input impedance of the control pins (big negative issue for me), but I presume that it is measured in kilo-ohms, not tera-ohms). And, I'm getting four linearized amplifiers from each 2164 this way as well, rather than the customary two.</span></div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024"></span> </div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024">I also (mostly now) use the 2164 as a four-quadrant (or variable-quadrant) multiplier, and it is not clear whether the 3364 is amenable to that application.</span></div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024"></span> </div><div dir="ltr" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span class="336201316-09082024">If I could get the AS3364 for less than $2 each, then I'd probably get more serious about using them.</span></div><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div dir="ltr" lang="en-us" class="OutlookMessageHeader" align="left" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><hr tabindex="-1"><font size="2" face="Tahoma"><b>From:</b><span class="Apple-converted-space"> </span>Synth-diy [<a href="mailto:synth-diy-bounces@synth-diy.org">mailto:synth-diy-bounces@synth-diy.org</a>]<span class="Apple-converted-space"> </span><b>On Behalf Of<span class="Apple-converted-space"> </span></b>mark verbos via Synth-diy<br><b>Sent:</b><span class="Apple-converted-space"> </span>Friday, August 09, 2024 8:50 AM<br><b>To:</b><span class="Apple-converted-space"> </span>Dan Snazelle<br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [sdiy] Best AVAILABLE OTA for building new designs?<br></font><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"></div><table style="caret-color: rgb(0, 0, 0); font-family: Helvetica; letter-spacing: normal; orphans: auto; text-transform: none; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; padding-left: 0px; border-collapse: collapse;"><tbody><tr><td><font style="padding: 3px; line-height: 1.6; background-color: rgb(255, 236, 179); font-style: normal; font-family: Arial, sans-serif; font-size: 12px; font-weight: normal;">[<strong>CAUTION:</strong><span class="Apple-converted-space"> </span>Non-UBC Email]</font></td></tr></tbody></table><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Dan,</span><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">I’ve been using the AS2164 only when I need the exponential response. If I need linear VCAs I now use the AS3364, which is more or less a clone of the SSM2024. That’s the same pinout more or less as the SSM2164 but has linear response. So, it’s very easy to use, pretrimmed, quiet, CV referenced to ground, summing node signal ins, doesn’t require all of those 560p caps. That works out great when lots of VCAs are needed, Some people were really turned off by the 1% harmonic distortion, but I have yet to notice an distortion on a synth circuit. </div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div style="display: block;"><div class="apple-rich-link" role="link" data-url="https://www.alfarzpp.lv/eng/sc/AS3364.pdf" draggable="true" style="display: inline-block; -webkit-user-select: all; -webkit-user-drag: element;"><a dir="ltr" class="lp-rich-link" role="button" href="https://www.alfarzpp.lv/eng/sc/AS3364.pdf" rel="nofollow" draggable="false" width="228" style="width: 228px; display: block; font-family: -apple-system, Helvetica, Arial, sans-serif; overflow: hidden; text-decoration: none; -webkit-user-select: none; border-radius: 10px; -webkit-user-modify: read-only;"><table class="lp-rich-link-emailBaseTable" border="0" cellspacing="0" cellpadding="0" width="228" style="background-color: rgb(229, 230, 233); width: 228px; border-collapse: collapse; font-family: -apple-system, Helvetica, Arial, sans-serif; table-layout: fixed;"><tbody><tr><td align="middle" vertical-align="center"><span id="cid:336201316@09082024-0D95"><preview.png></span></td></tr><tr><td vertical-align="center"><table class="lp-rich-link-captionBar" cellspacing="0" cellpadding="0" width="228" bgcolor="#e5e6e9" style="font-family: -apple-system, Helvetica, Arial, sans-serif; table-layout: fixed;"><tbody><tr><td class="lp-rich-link-captionBar-textStackItem" style="padding: 8px 0px;"><div class="lp-rich-link-captionBar-textStack" style="margin: 0px 16px; max-width: 100%; overflow: hidden;"><div class="lp-rich-link-captionBar-textStack-topCaption-leading" style="text-align: left; text-overflow: ellipsis; overflow-wrap: break-word; font-size: 12px; overflow: hidden; font-weight: 500;"><a href="https://www.alfarzpp.lv/eng/sc/AS3364.pdf" rel="nofollow" draggable="false" style="text-decoration: none;"><font color="#272727">AS3364</font></a></div><div class="lp-rich-link-captionBar-textStack-bottomCaption-leading" style="text-align: left; text-overflow: ellipsis; overflow-wrap: break-word; font-size: 11px; overflow: hidden; font-weight: 400;"><a href="https://www.alfarzpp.lv/eng/sc/AS3364.pdf" rel="nofollow" draggable="false" style="text-decoration: none;"><font color="#808080">PDF Document · 494 KB</font></a></div></div></td></tr></tbody></table></td></tr></tbody></table></a></div></div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">Mark</div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br id="lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>On Aug 8, 2024, at 8:08 PM, Dan Snazelle via Synth-diy <synth-diy@synth-diy.org> wrote:</div><br class="Apple-interchange-newline"><div><div dir="ltr"><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">imagine someone asked you to make some new synth modules.</div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">then imagine that the last time you did so in any quantity above one--- it was 2017. </div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">I am trying to get a handle on what the parts landscape is like now for cost-effective CV control. Back in 2017 the lm13700 was really the only available OTA . I was just starting to work with the ssm2164 at the time but never used it extensively.</div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">In the interim I have built synth circuits but only in quantities of one where cost was no object and I was able to rely on my own extensive parts supply. </div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">So my question is this-- if I am thinking about design for manufacturing<span class="_Entity _EType_OWA_HYPHEN _EId_OWA_HYPHEN_1 _EReadonly_1" style="display: inline-block;"><span id="hyphen2" class="hyphen">—</span></span>what do you think the best option is? </div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">Has anyone tried the quad ALFA OTA? Is it even readily available? Same for the new SSM2040. </div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">OR would you just use the 2164 instead? </div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">OR would you just try to make discrete OTAS out of say the BCM856DS //BCM847BS</div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;">thanks for any and all opinions on this. </div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="line-height: normal; margin: 0px; font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div><div class="elementToProof" style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt;"><br></div></div>________________________________________________________<br>This is the Synth-diy mailing list<br>Submit email to: Synth-diy@synth-diy.org<br>View archive at: https://synth-diy.org/pipermail/synth-diy/<br>Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy<br>Selling or trading? Use marketplace@synth-diy.org<br></div></blockquote></div><br></div><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">________________________________________________________</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">This is the Synth-diy mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Submit email to: Synth-diy@synth-diy.org</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">View archive at: https://synth-diy.org/pipermail/synth-diy/</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Selling or trading? Use marketplace@synth-diy.org</span></div></blockquote></div><br></div></body></html>