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Sender: "piclist-bounces@mit.edu" Date: Fri, 6 Aug 2021 11:38:46 -0700 Subject: Re: [EE] Latching relay ratings Thread-Topic: [EE] Latching relay ratings Thread-Index: AdeK85ch5l4vh/YsTx+YNIB1s7t4WQ== 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 209.85.166.42 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.166.42; helo=mail-io1-f42.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=VNeWLDY1wEvnlE8CevNlhbEV3vCsbDq1HIlj0KgA884=; b=JlVhnYrZkpTl5YghHDoY9uPriLwOVtiPhz502iGza9lgd+EZ7VBAytqnW14+gfYaVr Lg8Fb/VCJ+9XZMncGh/20U0vvw5AtSBnanUKeoj/8Isgg22IJV3s3uSNvSMgKt1zyn0O gozSxQpyPDJlxJgcyLlS/3jGBDGV7Uhxcv9AJG1rqPyOySijC5VK4AZqfHnPgCWYzYyH rtEPXn904nOHvTqhdkLaWndKTmLFsC+0WV8w5Su3EhYO0JTDHnxHH6uDyUG+SkR3tNAy wNFbc6qSFBVjMHM0Rs5nh8bF6g++OtGhaf43HQNp9aX2ohAhweEdGj96YQfBiXMPLitp /uXg== authentication-results: spf=pass (sender IP is 209.85.166.42) 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:a5d:8d0d:: with SMTP id p13mr202376ioj.129.1628275136103; Fri, 06 Aug 2021 11:38:56 -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 One more note here: It's not quite a "pet peeve" of mine, but the normal snubbing diode across the coil approach significantly slows down the coil release by allowing the current to flow longer. I've seen a 3-1 difference in opening time by using a high voltage transistor to drive the coil, and a Zener rated a bit lower (15%) than the VCE rating of the transistor, from collector to ground. YMMV, but when you're trying to avoid contact burning and welding, it matters. --=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 .