From: Jason White <whitewaterssoftwareinfo@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
Sender: "piclist-bounces@mit.edu" <piclist-bounces@mit.edu>
Date: Thu, 6 Feb 2020 08:15:10 -0800
Subject: [EE] PCB trace as a 1 Ohm resistor, Peak pulse 25amps (625W) for
 1ms?
Thread-Topic: [EE] PCB trace as a 1 Ohm resistor, Peak pulse 25amps (625W)
 for 1ms?
Thread-Index: AdXdCn4oRWJwyqyBRGiJkBzUm218uw==
Message-ID:
 <CAOFvGD4oQMganaSTJ7xn1+Y8+vDpOwD0su3XT=iNF0FqLVQ4UQ@mail.gmail.com>
Reply-To: Microcontroller discussion list - Public. <piclist@mit.edu>
Accept-Language: en-US
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
	209.85.167.182 as permitted sender) receiver=protection.outlook.com;
	client-ip=209.85.167.182; helo=mail-oi1-f182.google.com;
dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com;
 s=20161025;	h=mime-version:from:date:message-id:subject:to;
	bh=YDr3HoWyQxdL4V7fwrxcUDXBO+lctvsqxlx9bYsUZJ0=;
	b=qOhkViYEfRAG9PgyFoCE4getY7t+lVPubMDyPHYDoeJd8zrnXMjm2LoUPJMQo07wXB
	2LuBa79EyJxd/6CnvINsq8cPMImgpNwTGfXG3usCrnuqinWORPdFs88IZUjz2o8RHypj
	920Rn/gc0CorXmt7V1I93+KJEZs/9FFnabkuEB5VR8DgcICR4G06ygs9Xm288idyAl7I
	QwJPk2Lcvs/UOuODWf8a/HKvV1J8gtDUsMWk8NZApHgzjW/AWvi7iBNS3mE0QkDSohzF
	8dbEkF2//5WLza6GuRATPURuSpoE0/a0Ws25on6W4wDcwaTYgMxbanWc4YFgxSQQD0za	QYCA==
authentication-results: spf=pass (sender IP is 209.85.167.182)
	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;compauth=pass reason=100
errors-to: piclist-bounces@mit.edu
list-id: "Microcontroller discussion list - Public." <piclist.mit.edu>
list-post: <mailto:piclist@mit.edu>
x-beenthere: piclist@mit.edu
x-mailman-version: 2.1.6
x-received: by 2002:aca:5150:: with SMTP id
 f77mr7274303oib.52.1581005745004; 	Thu, 06 Feb 2020 08:15:45 -0800 (PST)
x-topics: [EE]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0

Hello everyone,

The Vishay D/CRCW e3 SMT resistor family spec. says that one of their
1 ohm 2512 resistors is rated to withstand a 1ms pulse of 40W (6.32
amps) 8000 times. I have an application when I need to push a bit more
than 25 amps through a 1 ohm resistor for 1ms which is a roughly 625W
pulse. Low duty cycle, only needs to survive 1000 times total.

I am looking for a small, lightweight solution that won't affect
vibration testing. Big through hole resistors are frowned upon due to
their mass and height. A TO-220 on its back might be acceptable but
they don't seem to have what it takes power wise. With few other
options I am considering using PCB trace resistance as my 1 ohm
resistor. The trouble it is difficult to calculate the transient
thermal response of a PCB trace on FR-4 material to determine the
required width and length.

Does anyone have any advice about handling this pulse?

--=20
Jason White
--=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
.