Received: from PCH.mit.edu (18.7.21.50) by mail.efplus.com (192.168.0.8) with Microsoft SMTP Server (TLS) id 8.3.485.1; Tue, 5 Oct 2021 13:06:16 -0700 Received: from PCH.MIT.EDU (localhost.localdomain [127.0.0.1]) by PCH.mit.edu (8.14.7/8.12.8) with ESMTP id 195JsvYA031756; Tue, 5 Oct 2021 15:55:56 -0400 Received: from outgoing-exchange-3.mit.edu (OUTGOING-EXCHANGE-3.MIT.EDU [18.9.28.13]) by PCH.mit.edu (8.14.7/8.12.8) with ESMTP id 195Jsugw031753 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Tue, 5 Oct 2021 15:54:57 -0400 Received: from oc11exedge2.exchange.mit.edu (OC11EXEDGE2.EXCHANGE.MIT.EDU [18.9.3.18]) by outgoing-exchange-3.mit.edu (8.14.7/8.12.4) with ESMTP id 195Jsqoi025205 for ; Tue, 5 Oct 2021 15:54:56 -0400 Received: from w92expo32.exchange.mit.edu (18.7.74.44) by oc11exedge2.exchange.mit.edu (18.9.3.18) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 5 Oct 2021 15:54:15 -0400 Received: from w92exhyb8.exchange.mit.edu (18.7.71.113) by w92expo32.exchange.mit.edu (18.7.74.44) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 5 Oct 2021 15:54:37 -0400 Received: from NAM12-DM6-obe.outbound.protection.outlook.com (104.47.59.173) by w92exhyb8.exchange.mit.edu (18.7.71.113) with Microsoft SMTP Server (TLS) id 15.0.1497.23 via Frontend Transport; Tue, 5 Oct 2021 15:54:37 -0400 Received: from BN6PR13CA0008.namprd13.prod.outlook.com (2603:10b6:404:10a::18) by PH0PR01MB6539.prod.exchangelabs.com (2603:10b6:510:96::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4566.19; Tue, 5 Oct 2021 19:54:35 +0000 Received: from BN8NAM11FT013.eop-nam11.prod.protection.outlook.com (2603:10b6:404:10a:cafe::7a) by BN6PR13CA0008.outlook.office365.com (2603:10b6:404:10a::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4587.9 via Frontend Transport; Tue, 5 Oct 2021 19:54:35 +0000 Received: from mail-qk1-f175.google.com (209.85.222.175) by BN8NAM11FT013.mail.protection.outlook.com (10.13.176.182) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4566.14 via Frontend Transport; Tue, 5 Oct 2021 19:54:35 +0000 Received: by mail-qk1-f175.google.com with SMTP id 72so165720qkk.7 for ; Tue, 05 Oct 2021 12:54:35 -0700 (PDT) From: Denny Esterline To: Microcontroller discussion list - Public. Sender: "piclist-bounces@mit.edu" Date: Tue, 5 Oct 2021 12:54:23 -0700 Subject: Re: [EE] Why is FRAM (Ferromagnetic RAM) common on TI microcontrollers but not others? Thread-Topic: [EE] Why is FRAM (Ferromagnetic RAM) common on TI microcontrollers but not others? Thread-Index: Ade6JHUl61M4LGnhS1GR9MfdVCpysA== 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 209.85.222.175 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.222.175; helo=mail-qk1-f175.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=VxM7wBpZAzhYWqTdVJROXJ0YsnGFpSdXuANkjElH4CA=; b=jM0vEZIab2DQr6WdyV4VFOK9Nx/p7zW5WjQq8nBevqLxnQjAmUaGzQyWADtib77bXK p49E6UqjaP3J6/3TKWOZft1SrfI1Ve6AzsU2zkyADiha5HIQFNvXjUZWgf1qlFGpD+yy ttbyVv7iu9ISf56bnnBU5qKaCO6cwK3xTrxY4JDim7ZmEag096XDvmJqrxTsQRVM3/nD 4JQEBTQJEZXXTaYDJZRsTl0FtSgEPXxOI9jPIJm06+4e5MF7t8Zk6DZqbJNrLDbomrXd 0V8T6SyVCx2FA0e36lHUpzoCQZqgUgCI0kLQ1Rou8Xvlrwj/ug0gBLJLD5wVJC+B46AI j3rA== authentication-results: spf=pass (sender IP is 209.85.222.175) 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:a37:a495:: with SMTP id n143mr16761333qke.339.1633463675165; Tue, 05 Oct 2021 12:54:35 -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 My information is easily several years out of date at this point, but I believe there is (was?) still patents covering some aspects of FRAM. A few years ago RAMTRON [bought | sold | taken over | joined] Cypress semiconductor and somewhere in that mess, TI seems to have started producing FRAM based parts. It's a incestious industry and I can't keep track of all the mergers and acquisitions. -Denny On Tue, Oct 5, 2021 at 11:26 AM Jason White < whitewaterssoftwareinfo@gmail.com> wrote: > Hi, > > Recently, I got my first exposure to a MSP430 with 256kB FRAM > (Ferromagnetic RAM). The FRAM can be read and written at a rate of > 8MHz (one word per clock cycle). It appears to have "pretty good" > cycle endurance, data retention, and power consumption. For me, this > begs the question: > > Why isn't FRAM more popular? Cost? Patents? Performance? > > -- > Jason White > -- > 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 .