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Sender: "piclist-bounces@mit.edu" Date: Sun, 16 Feb 2020 15:48:05 -0800 Subject: Re: [EE] large USB power banks Thread-Topic: [EE] large USB power banks Thread-Index: AdXlJXGJFZrCq0eSTv2mvdWWXK8f6w== Message-ID: <20200216234805.GC16626@laptop.org> References: <15c8c6b973b5343c2becb83c6d63a638@mtlp000086> 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 laptop.org designates 209.85.214.179 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.214.179; helo=mail-pl1-f179.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=laptop-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=b/DSWltUvXNyuwAcjFsrCRhSmkRE3u66OcUtyJZee9I=; b=B+OPeD/bRg3x8PgCLLn/kKZy7o44DEEpHZaJmysD5Jf/+B3NUk7PdTNhvjCa6XePZh YfaVyazr/zo+T092rGLVSS/kODSRYnzTe8TF+7CsVrYOeWDY4Os0miSJp+rlyXvanRpY 8oEzzgREETHrUm0rU4ih0TgAKR0y+De9SntyNnlczVNie/TDWLoGUBefvE4JMzHtPv7m kHcTgTmWsinEZ6giohwkKhsY9F66v8tAotXoNfKYzRRa1dXsGoVrTYMfmViaa5yaNCkN gPtRvTCjhaSKZsHPr7bguhOGo5jogY+zZafZu+ycdxu3JCvWv8/6+SvNxhF3o64OZO4c V4mQ== authentication-results: spf=pass (sender IP is 209.85.214.179) smtp.mailfrom=laptop.org; mit.edu; dkim=pass (signature was verified) header.d=laptop-org.20150623.gappssmtp.com; mit.edu; dmarc=bestguesspass action=none header.from=laptop.org;compauth=pass reason=109 user-agent: Mutt/1.9.4 (2018-02-28) 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:a17:90a:ca12:: with SMTP id x18mr16658552pjt.66.1581896890668; Sun, 16 Feb 2020 15:48:10 -0800 (PST) x-topics: [EE] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 I've also used single cell USB power banks in some quick hacks. Where I've wanted less than 5V, I've taken power directly from the cell terminals on the PCB. This defeats the discharge protection, so you have to add your own, or procedures. It can also confuse any coulomb counter in the pack. --=20 James Cameron http://quozl.netrek.org/ --=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 .