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Sender: "piclist-bounces@mit.edu" Date: Sat, 12 Sep 2020 18:54:23 -0700 Subject: Re: [EE] Four Layer Routing Strategy Thread-Topic: [EE] Four Layer Routing Strategy Thread-Index: AdaJclsiJqVjzFzjTZiOOH2ecrh7Eg== 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: Pass X-MS-Exchange-Organization-PRD: mit.edu X-MS-TNEF-Correlator: received-spf: Pass (protection.outlook.com: domain of gmail.com designates 209.85.166.49 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.166.49; helo=mail-io1-f49.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=uPTMZ3RzTafMlXhjyH9wZoE4QPJOGSf6mmQdH+2fLkE=; b=YREHtJBCgC1hsp2nczs5pucCZQwntI/eGW4+ZqQX4LkCEPWqgdaYhK2t1v1OlmUGzy eJrC1Hu/ETfwUoo1Ijuab9EHUoN1QHNqprNWmMY5eJKFIveo6uAs9BXWyYEy167sXq2t Yu3WZt1Erq/aBP4Ir2agzP0IN3E0xmMUJ7rqVqk/sriQpZ8gMJLHB+8umcktiUyCoHuv wEVxaX0VmKqR6TIjJ8DLFsDuSzkntoafwJn6FvTm80ISAfUwXU8HVcy8vnicbR3YVHg4 TIsiIyxhNUAGPieQz3j6fg8HAiTu51HbSg6pNQ2CegbfEJgs77I3oB/eTbDrAeogVBom 9eoA== authentication-results: spf=pass (sender IP is 209.85.166.49) 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; 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:a05:6602:2f8a:: with SMTP id u10mr6808088iow.72.1599962089011; Sat, 12 Sep 2020 18:54:49 -0700 (PDT) x-topics: [EE] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Thank you all for the advice! Ok, sounds like keeping the inner layers as ground and 3.3V separately will be the best. No problems there. One thing about planes though, I once read an article about being careful using planes, that essentially small ground loops could form in them. Since then I've always had my planes as a separate net (ie not ground), and I connected them to the ground traces strategically. Each area of pour had only one connection to ground. Should I be using the pours a bit more liberally and letting them join all the pins on that actual net? That's easily done (actually easier than the way I have been doing it). I'd add thermals in to try to help make it easier to solder. The board service I've been using lately doesn't allow for blind/buried vias without a hefty upcharge. I am definitely not at that level, that's for sure! Thank you! Josh --=20 A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. -Douglas Adams --=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 .