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Sender: "piclist-bounces@mit.edu" Date: Tue, 26 May 2020 10:43:39 -0700 Subject: Re: [EE] Placement of LED resistor Thread-Topic: [EE] Placement of LED resistor Thread-Index: AdYzhlYIkUTLtSgNRUi85zzAz6RAKQ== Message-ID: References: List-Help: List-Subscribe: , List-Unsubscribe: , In-Reply-To: Reply-To: Microcontroller discussion list - Public. Accept-Language: en-US X-MS-Exchange-Organization-AuthAs: Anonymous X-MS-Exchange-Organization-AuthSource: TS500.efplus4.local X-MS-Has-Attach: X-Auto-Response-Suppress: All X-MS-Exchange-Organization-SenderIdResult: TempError X-MS-Exchange-Organization-PRD: mit.edu X-MS-TNEF-Correlator: received-spf: Pass (protection.outlook.com: domain of gmail.com designates 209.85.221.48 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.221.48; helo=mail-wr1-f48.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=sgEHMkpQlcXfym4yPwW/enkFOifpIGemOTf4qRqRLCA=; b=HjnYlhZgrjvYYagllrxeXgfZzCixVZ+Ne7cvfEksYPlhwuLF//tAoDRtRhCzzrhoP/ VK3yR9/QfmN34CvaM2jv9FqJYN3mw4JWQrf13yGxdWoEDI4+ApS+G52bHscEnhDXyx8f ePlTm5vKuHEpV0+EFVoUagZszGYixX52LYdp3kAXcEtWISim4vVzo9ArErdGEsLbuKjQ L4aePhZ1RkNLNwjwbdqRJK6VN7+G1dfS7kUYvulzpLhjyoAEpSpLNH5p3OjFdbup6o91 GxFytTbmFvtYpqcLy9kXE3/Q81CyKyrfvCvYyKQS2/gkjescANfOZE0u/KgV4sYJ9lyn nwmQ== authentication-results: spf=pass (sender IP is 209.85.221.48) smtp.mailfrom=gmail.com; mit.edu; dkim=pass (signature was verified) header.d=gmail.com;mit.edu; dmarc=pass action=none header.from=gmail.com;compauth=pass reason=100 errors-to: piclist-bounces@mit.edu list-id: "Microcontroller discussion list - Public." list-post: x-beenthere: piclist@mit.edu x-mailman-version: 2.1.6 x-received: by 2002:a5d:40d2:: with SMTP id b18mr18176897wrq.131.1590514926360; Tue, 26 May 2020 10:42:06 -0700 (PDT) x-topics: [EE] x-content-filtered-by: Mailman/MimeDel 2.1.6 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 In normal, everyday operation - it does not matter at all. There are some unusual corner cases where it might matter, but frankly, if you're asking the question, those corner cases are outside your scope. I'm thinking things like multiplexed pin functionality, short circuit planning, etc. On Tue, May 26, 2020 at 10:25 AM Lindy Mayfield wrote: > Hello, > > In what circumstances does it matter if a current resisting LED resistor > is attached between positive source to LED anode or from LED cathode to > ground? > > Thanks very much! > Kind regards, > Lindy > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .