<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body>
    <div class="moz-cite-prefix">
      <p>Yes, the FET reverse diode will go into conduction at about
        -0.5-0.6V. So maybe 1 to 1.2Vpp. </p>
      <p>If what is driving the headphone amp is 2Vpp, and the output
        was open (or light load), it could clip. <br>
      </p>
      <p>The 22R resistors form a voltage divider together with the
        other 22R and the load. <br>
      </p>
      <p>So the actual clipping level depends on the headphones
        connected. </p>
      <p>Assuming you don't run this full steam it's probably good
        enough. <br>
      </p>
      <p>Not a great solution, but it works aparrently. <br>
      </p>
      <p><br>
      </p>
      <p>I would have used two NMOS in anti-series instead.<br>
      </p>
      <p>No need for exotic components or PMOS (which would just flip
        the sign) as discussed.<br>
      </p>
      <p><br>
      </p>
      <p>Best,</p>
      <p> René<br>
      </p>
    </div>
    <div class="moz-cite-prefix"><br>
    </div>
    <div class="moz-cite-prefix"><br>
    </div>
    <div class="moz-cite-prefix">On 24.04.2024 22:14, Chris McDowell via
      Synth-diy wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:58FD7D2B-88E6-4342-9F46-5CDDBEA0DA95@gmail.com">
      <meta http-equiv="content-type" content="text/html; charset=UTF-8">
      <div>
        <div style="display: block;" class="">
          <div
style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;"
            class="apple-rich-link" draggable="true" role="link"
data-url="https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf"><a
style="border-radius:10px;font-family:-apple-system, Helvetica, Arial, sans-serif;display:block;-webkit-user-select:none;width:300px;user-select:none;-webkit-user-modify:read-only;user-modify:read-only;overflow:hidden;text-decoration:none;"
              class="lp-rich-link" rel="nofollow"
href="https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf"
              dir="ltr" role="button" draggable="false" width="300"
              moz-do-not-send="true">
              <table
style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:#E9E9EB;font-family:-apple-system, Helvetica, Arial, sans-serif;"
                class="lp-rich-link-emailBaseTable" width="300"
                cellspacing="0" cellpadding="0" border="0">
                <tbody>
                  <tr>
                    <td vertical-align="center" align="center"><img
style="width:300px;filter:brightness(0.97);height:199px;"
                        draggable="false"
                        class="lp-rich-link-mediaImage"
                        alt="preview.png"
                        src="cid:part1.GtsAS80m.fRbHFwtK@schmitzbits.de"
                        width="300" height="199"></td>
                  </tr>
                  <tr>
                    <td vertical-align="center">
                      <table
style="font-family:-apple-system, Helvetica, Arial, sans-serif;table-layout:fixed;background-color:rgba(233, 233, 235, 1);"
                        class="lp-rich-link-captionBar" width="300"
                        cellspacing="0" cellpadding="0"
                        bgcolor="#E9E9EB">
                        <tbody>
                          <tr>
                            <td style="padding:8px 0px 8px 0px;"
class="lp-rich-link-captionBar-textStackItem">
                              <div
style="max-width:100%;margin:0px 16px 0px 16px;overflow:hidden;"
class="lp-rich-link-captionBar-textStack">
                                <div
style="word-wrap:break-word;font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left;"
class="lp-rich-link-captionBar-textStack-topCaption-leading"><a
                                    rel="nofollow"
href="https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf"
                                    style="text-decoration: none"
                                    draggable="false"
                                    moz-do-not-send="true"><font
                                      style="color: rgba(0, 0, 0, 1);"
                                      color="#000000">MiniBrute-10-OUTPUT</font></a></div>
                                <div
style="word-wrap:break-word;font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left;"
class="lp-rich-link-captionBar-textStack-bottomCaption-leading"><a
                                    rel="nofollow"
href="https://hackabrute.yusynth.net/MINIBRUTE/digital-board/schematics/MiniBrute-10-OUTPUT.pdf"
                                    style="text-decoration: none"
                                    draggable="false"
                                    moz-do-not-send="true"><font
style="color: rgba(60, 60, 67, 0.6);" color="#A2A2A9">PDF Document · 339
                                      KB</font></a></div>
                              </div>
                            </td>
                          </tr>
                        </tbody>
                      </table>
                    </td>
                  </tr>
                </tbody>
              </table>
            </a></div>
        </div>
        <br>
      </div>
      <div><br>
      </div>
      <div>hello list, I've been looking at minibrute schematics today
        and I'm puzzled by the anti pop circuitry in the headphone
        driver. it -seems- like the body diode of the mosfets would
        conduct when the signal went below 0.6ish volts (something I've
        run into this using mosfets for dc signal muting).</div>
      <div><br>
      </div>
      <div> From the vca page, that signal can be up to 2Vpp.  <a
href="https://hackabrute.yusynth.net/MINIBRUTE/analog-board/schematics/MiniBrute-08-VCA.pdf"
          moz-do-not-send="true" class="moz-txt-link-freetext">https://hackabrute.yusynth.net/MINIBRUTE/analog-board/schematics/MiniBrute-08-VCA.pdf</a></div>
      <div><br>
      </div>
      <div>What am I missing here? Is 2Vpp just fine in this case? Now
        reading the 2n7002 datasheet I see the forward voltage of the
        source-drain diode is typ 0.88V, 1.5V max. Did I just answer my
        own question? 😜</div>
    </blockquote>
    <br>
    <p><br>
    </p>
    <blockquote type="cite"
      cite="mid:58FD7D2B-88E6-4342-9F46-5CDDBEA0DA95@gmail.com"><br
        id="lineBreakAtBeginningOfSignature">
      <div dir="ltr">Cheers,
        <div>Chris McDowell</div>
      </div>
      <br>
      <fieldset class="moz-mime-attachment-header"></fieldset>
      <pre class="moz-quote-pre" wrap="">________________________________________________________
This is the Synth-diy mailing list
Submit email to: <a class="moz-txt-link-abbreviated" href="mailto:Synth-diy@synth-diy.org">Synth-diy@synth-diy.org</a>
View archive at: <a class="moz-txt-link-freetext" href="https://synth-diy.org/pipermail/synth-diy/">https://synth-diy.org/pipermail/synth-diy/</a>
Check your settings at: <a class="moz-txt-link-freetext" href="https://synth-diy.org/mailman/listinfo/synth-diy">https://synth-diy.org/mailman/listinfo/synth-diy</a>
Selling or trading? Use <a class="moz-txt-link-abbreviated" href="mailto:marketplace@synth-diy.org">marketplace@synth-diy.org</a>
</pre>
    </blockquote>
    <p><br>
    </p>
    <pre class="moz-signature" cols="72">-- 
--
<a class="moz-txt-link-abbreviated" href="mailto:synth@schmitzbits.de">synth@schmitzbits.de</a>
<a class="moz-txt-link-freetext" href="http://schmitzbits.de">http://schmitzbits.de</a></pre>
  </body>
</html>