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Sender: "piclist-bounces@mit.edu" Date: Tue, 21 Apr 2020 00:31:25 -0700 Subject: Re: [EE] LDO reg keeps failing. Looking for suggestions. Thread-Topic: [EE] LDO reg keeps failing. Looking for suggestions. Thread-Index: AdYXsBycAwxeCt47Ti21WaGWUoL9+Q== Message-ID: References: <35716fec-1512-6e55-8b3c-d4fe3e9b10aa@gmail.com> 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 209.85.208.54 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.208.54; helo=mail-ed1-f54.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cornell.edu; s=g.20171207; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=Nm5r8OtU+vdmhapNRIUn3OLO4f2o07hWmVzrPdua6/0=; b=kw/12BosxmF7O+8rzeefWwmmWwRTqJln0atj57oYipRAwvOh7e71yQazH+RHnxxa/L MxmiQSQI3wHUkzLnyAQ5ZxCushc/hnV9ddHDzUuxpdFzw0EcIGshkbEa5Ms7kLJbhylL cvM4FyQ4fsJbqvJn0cMsNGFJtVBvcCVGPX9IY2Dpg+OA0IE9KqnYkKr+J1xTnWOYlb0A 5080EZFFGfz4YsLrIVARmj1TpRcLpTaYZE4htkpkQ9YBYpA+y5OyLv+O8MQ2lgLpd7gn KJaMi/H9EipHn0OqmGUO8e1q4XpGvrsr+ScysvjeLAvB7fSiOxwX5OMN33w0vpx6r8UB TVhw== authentication-results: spf=pass (sender IP is 209.85.208.54) smtp.mailfrom=gmail.com; mit.edu; dkim=pass (signature was verified) header.d=cornell.edu;mit.edu; dmarc=pass action=none header.from=cornell.edu;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:aa7:d60a:: with SMTP id c10mr18062351edr.66.1587454296998; Tue, 21 Apr 2020 00:31:36 -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 On Mon, Apr 20, 2020 at 9:33 PM David Van Horn < david.vanhorn@backcountryaccess.com> wrote: > I disagree. > The failure mechanism is well documented, where Vout > Vin. > The point of D8 is to prevent the input pin from being more than a diode > drop below Vout in that situation. > But the problem mechanism here isn't Vin falling, it's Vout rising. > > Why do you say that the problem is Vout rising? It appears to me that Vou= t only powers the microcontroller, not the motors. Any regeneration from the motors should go directly into the battery. --=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 .