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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Coolio, I’ve ordered a load, so it’s working <span style='font-family:"Apple Color Emoji"'>😉</span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'>Rob Spencer<o:p></o:p></span></p></div></div><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'>07590 267835<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.5pt;color:black'><img width=202 height=45 style='width:2.1041in;height:.4687in' id="Picture_x0020_1" src="cid:image001.png@01D3D7EF.05BD3D40" alt="/Users/Rob/Library/Containers/com.microsoft.Outlook/Data/Library/Caches/Signatures/signature_1662765180"><o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:12.0pt;color:black'>From: </span></b><span style='font-size:12.0pt;color:black'><navelludd@gmail.com> on behalf of Mattias Rickardsson <mr@analogue.org><br><b>Date: </b>Thursday, 19 April 2018 at 14:47<br><b>To: </b>Rob Spencer <rob@gmsn.co.uk><br><b>Cc: </b>Tim Ressel <timr@circuitabbey.com>, Synth DIY <synth-diy@synth-diy.org><br><b>Subject: </b>Re: [sdiy] Happenin' new opamp<o:p></o:p></span></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><a name="_MailOriginalBody">Share it if you wish! </a><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:#222222;background:white'>John Caldwell</span></span><span style='mso-bookmark:_MailOriginalBody'> said:<o:p></o:p></span></p><div><p class=MsoNormal><span style='mso-bookmark:_MailOriginalBody'>"Feel free to leak the secret, if it means more people buy my part then I’m happy :-) "<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='mso-bookmark:_MailOriginalBody'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='mso-bookmark:_MailOriginalBody'>/mr<o:p></o:p></span></p></div></div><div><p class=MsoNormal><span style='mso-bookmark:_MailOriginalBody'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='mso-bookmark:_MailOriginalBody'>On 19 April 2018 at 15:44, Rob Spencer <</span><a href="mailto:rob@gmsn.co.uk" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>rob@gmsn.co.uk</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'>> wrote:<o:p></o:p></span></p><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>Good to know! Would you mind I if share this on the GMSN forum? <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p><div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:10.5pt;color:black'>Rob Spencer</span><o:p></o:p></span></p></div></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:10.5pt;color:black'>07590 267835</span><o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:10.5pt;color:black'><img border=0 width=202 height=45 style='width:2.1041in;height:.4687in' id="m_-5780210040590118938Picture_x0020_1" src="cid:image002.png@01D3D7EF.05BD3D40" alt="/Users/Rob/Library/Containers/com.microsoft.Outlook/Data/Library/Caches/Signatures/signature_768746585"></span><o:p></o:p></span></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><b><span style='font-size:12.0pt;color:black'>From: </span></b></span><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;color:black'>Synth-diy <</span></span><a href="mailto:synth-diy-bounces@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt'>synth-diy-bounces@synth-diy.org</span></span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;color:black'>> on behalf of Mattias Rickardsson <</span></span><a href="mailto:mr@analogue.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt'>mr@analogue.org</span></span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;color:black'>><br><b>Date: </b>Thursday, 19 April 2018 at 14:16<br><b>To: </b>Tim Ressel <</span></span><a href="mailto:timr@circuitabbey.com" target="_blank"><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt'>timr@circuitabbey.com</span></span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;color:black'>><br><b>Cc: </b>Synth DIY <</span></span><a href="mailto:synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt'>synth-diy@synth-diy.org</span></span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;color:black'>><br><b>Subject: </b>Re: [sdiy] Happenin' new opamp</span><o:p></o:p></span></p></div><div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><a name="m_-5780210040590118938__MailOriginalBody">I'm throwing in some news (for me at least) about the fairly new OPA1678/79 low-noise </a></span><span style='mso-bookmark:m_-5780210040590118938__MailOriginalBody'></span><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:#222222;background:white'>rail-to-rail</span> </span><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:#222222;background:white'>FET-input </span>op-amps that I was trying as substitutes for the OPA1652/54, which has a price more than twice as high. The specifications are remarkably similar, and by accident I got in contact with TI's </span><span style='mso-bookmark:_MailOriginalBody'><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:#222222;background:white'>John Caldwell. He writes:</span><o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>"I’ll let you in a on a little secret, the silicon is identical between the two devices. OPA1652 was released by another engineer before me, and when I took over the portfolio of audio op amps I personally felt that OPA1652 was too expensive to address the bulk of audio opportunities. For that reason, we made some changes to the production testing (used new test hardware that let us test more units faster) to reduce the manufacturing cost and re-released the device at a lower price point.<br>Fun fact: the OPA1652 / OPA1678 has the lowest broadband voltage noise of any FET-type input amplifier in TI’s portfolio. It even has lower broadband voltage noise than the much more expensive OPA827."<o:p></o:p></span></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>I don't know if this was known before, but anyway great to have the same brilliant chip for a fraction of the price... and isn't it a great attitude about quality product sales? :-)<o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>Regarding the inputs, which they don't mention being FET in the OPA1678 datasheet:<o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>"We received your feedback on the OPA1678 datasheet. With regards to mentioning the input device type, the OPA1678 is fabricated on a CMOS process, so yes the device type is indeed a FET (MOSFET). This is also shown in the simplified diagram of the internal architecture on the first page.<br>Calling it a “FET” input sometimes raises confusion between whether or not the devices is JFET or CMOS and I wanted to avoid that when I wrote the OPA1678 datasheet."<o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>/mr<o:p></o:p></span></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'><br><br>On 4 June 2017 at 17:39, Tim Ressel <</span><a href="mailto:timr@circuitabbey.com" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>timr@circuitabbey.com</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'>> wrote:<br>><br>> I started out with the LM4562. Very nice, but as you say, high cabbage factor. Then I went to the LME49723. Noise is higher but amp is cheaper. If you really want to break the bank, go with the AD797. Super low noise, super high price.<br>><br>> --timbo<br>><br>><br>> On 6/4/2017 2:29 AM, John P Shea wrote:<br>><br>> 4x the price:<br>><br>> </span><a href="http://www.ti.com/lit/ds/symlink/lm4562.pdf" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://www.ti.com/lit/ds/symlink/lm4562.pdf</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>><br>> DIP & SOIC<br>><br>> Regards,<br>> JPS<br>><br>> On Sun, 4 Jun 2017 at 12:21 pm, Tim Ressel <</span><a href="mailto:timr@circuitabbey.com" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>timr@circuitabbey.com</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'>> wrote:<br>>><br>>> It seems to be a popular amp. Mouser got 2500 of the SOICs in and blew<br>>> through them in days. They have 7K on order. I think they will become my<br>>> go-to amp for audio stuff. I'd write TI and ask for the QFN package.<br>>><br>>> --tim<br>>><br>>><br>>> On 5/24/2017 10:09 AM, </span><a href="mailto:paula@synth.net" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>paula@synth.net</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'> wrote:<br>>> > Tim,<br>>> ><br>>> > hey that's neat, though I feel the reverse, s shame it's not in a<br>>> > smaller 3x3 QFN package. The VSSOP is close though.<br>>> ><br>>> > Thanks for the heads up :)<br>>> ><br>>> > Paula<br>>> ><br>>> ><br>>> > On 2017-05-23 21:30, Tim Ressel wrote:<br>>> >> Hey,<br>>> >><br>>> >> Writing to say the OPA1678 from TI is a pretty nice little amp. Low<br>>> >> noise, low distortion, low bias current, low cost. Is a dual; OPA1679<br>>> >> is a quad. SMT only, sad to say, but that be the times we live in.<br>>> >><br>>> >> </span><a href="http://www.ti.com/lit/ds/symlink/opa1678.pdf" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://www.ti.com/lit/ds/symlink/opa1678.pdf</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>>> > _______________________________________________<br>>> > Synth-diy mailing list<br>>> > </span><a href="mailto:Synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>Synth-diy@synth-diy.org</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>>> > </span><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://synth-diy.org/mailman/listinfo/synth-diy</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>>> ><br>>><br>>> --<br>>> --Tim Ressel<br>>> Circuit Abbey<br>>> </span><a href="mailto:timr@circuitabbey.com" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>timr@circuitabbey.com</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>>><br>>> _______________________________________________<br>>> Synth-diy mailing list<br>>> </span><a href="mailto:Synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>Synth-diy@synth-diy.org</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>>> </span><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://synth-diy.org/mailman/listinfo/synth-diy</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>><br>><br>><br>> _______________________________________________<br>> Synth-diy mailing list<br>> </span><a href="mailto:Synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>Synth-diy@synth-diy.org</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>> </span><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://synth-diy.org/mailman/listinfo/synth-diy</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>><br>><br>> -- <br>> --Tim Ressel<br>> Circuit Abbey<br>> </span><a href="mailto:timr@circuitabbey.com" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>timr@circuitabbey.com</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>><br>><br>> _______________________________________________<br>> Synth-diy mailing list<br>> </span><a href="mailto:Synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>Synth-diy@synth-diy.org</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>> </span><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://synth-diy.org/mailman/listinfo/synth-diy</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'><br>><o:p></o:p></span></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='mso-bookmark:_MailOriginalBody'>_______________________________________________ Synth-diy mailing list </span><a href="mailto:Synth-diy@synth-diy.org" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>Synth-diy@synth-diy.org</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'> </span><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank"><span style='mso-bookmark:_MailOriginalBody'>http://synth-diy.org/mailman/listinfo/synth-diy</span><span style='mso-bookmark:_MailOriginalBody'></span></a><span style='mso-bookmark:_MailOriginalBody'> <o:p></o:p></span></p></div></div></div></div></blockquote></div><span style='mso-bookmark:_MailOriginalBody'></span><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>