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Article #2404Re: Elantec EL2142C line receiver latchup problem
From: Peter H
Date: Mon, 08 Apr 2002 11:38
Date: Mon, 08 Apr 2002 11:38
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Your inputs may be going outside the allowable common mode range. This may happen if you are dc coupled to the transmitter and a long cable. Is your transmitter on the same power supply? Not knowing your transmit circuit, the sample circuit is somewhat simplified - input bias dc currents? - make sure you have dc paths eg 100kohms to ground for the inputs of the el2142. Maybe also try ac couple your input signal/s. I didn't have any problems with 800m of CAT5. Peter H "David L. Jones" <dljones@ozemail.com.au> wrote in message news:734fad6f.0204072142.5b3c9d7e@posting.google.com... > Has anyone had any problems with the inputs on the Elantec EL2142C > diff line receiver latching up and causing excess current drain? > I appear to be having this problem, and the chip is drawing up to an > extra 100mA for some reason. > I'm using the device in the standard twisted pair application as shown > in the data sheet (single resistor feedback), with a terminated diff > input (but no signal connected). The current drops back to normal if I > single-end one of the inputs to ground. > It's not the chip, I've changed it, power rails are clean and > decoupled, no oscillation, Vref at ground, and the output is not > driving any significant load. > > Any ideas? > > Thanks > Dave :)
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 112d1e,3995c030be69f7b2 X-Google-Attributes: gid112d1e,public X-Google-Thread: 103407,3995c030be69f7b2 X-Google-Attributes: gid103407,public X-Google-Thread: 1118be,3995c030be69f7b2 X-Google-Attributes: gid1118be,public X-Google-ArrivalTime: 2002-04-08 04:39:00 PST Path: arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news1.optus.net.au!optus!intgwlon.nntp.telstra.net!news.telstra.net!newsfeeds.bigpond.com!not-for-mail From: "Peter H" <plowthruremovethis@bigpond.com> Newsgroups: sci.electronics.design,sci.electronics.components,aus.electronics References: <734fad6f.0204072142.5b3c9d7e@posting.google.com> Subject: Re: Elantec EL2142C line receiver latchup problem Lines: 34 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Message-ID: <cefs8.32059$uR5.77097@newsfeeds.bigpond.com> Date: Mon, 8 Apr 2002 21:08:58 +0930 NNTP-Posting-Host: 144.134.8.230 X-Trace: newsfeeds.bigpond.com 1018265608 144.134.8.230 (Mon, 08 Apr 2002 21:33:28 EST) NNTP-Posting-Date: Mon, 08 Apr 2002 21:33:28 EST Organization: Telstra BigPond Internet Services (http://www.bigpond.com)