SparkFun Electronics Commentsurn:uuid:214d0e4e-f1b1-d287-ce26-ac5b4c9f82492024-03-28T11:11:19-06:00SparkFun ElectronicsEmotion on RTL-10774 - Touch Sense Shield RetailEmotionurn:uuid:147d04e9-42f8-70d2-9bbc-70a8cd26a29e2012-01-27T13:24:00-07:00<p>What is the magic by which one of the red leds is glowing yellow?</p>
WimL on RTL-10774 - Touch Sense Shield RetailWimLurn:uuid:c2610537-9ae1-47fc-f846-7d657baa27c22012-01-12T15:40:33-07:00<p>Those are logic-level translators. It's a super-simple way to do bidirectional level translation on an open-drain line. I can't find the nice appnote that TI (I think) had on the technique, but here's an <a href="http://www.maxim-ic.com/app-notes/index.mvp/id/1159" rel="nofollow">article from Maxim</a>.</p>
nickhudspeth on RTL-10774 - Touch Sense Shield Retailnickhudspethurn:uuid:289624ca-17dd-db27-e2a6-f95529b1bc3b2011-12-02T23:12:57-07:00<p>What is the purpose of the BSS138s on the SCL and SDA lines?</p>