Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: "Don" Newsgroups: sci.electronics.design Subject: Re: Converting a NTC voltage into temperature in Celcius Date: Fri, 11 Apr 2025 15:50:44 -0000 (UTC) Organization: A noiseless patient Spider Lines: 40 Message-ID: <20250411c@crcomp.net> References: <67f4f23c$0$11449$426a74cc@news.free.fr> <879d5bd8-a857-e5f8-e9a5-f3c004fbb937@electrooptical.net> <20250410c@crcomp.net> <20250411b@crcomp.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Fri, 11 Apr 2025 17:50:44 +0200 (CEST) Injection-Info: dont-email.me; posting-host="1fac91ad0d4b3ee4c0f74f33e0c33964"; logging-data="2104534"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX195xGJlKoH+q5gxpFHVawH1" Cancel-Lock: sha1:iBaR8JmRt79JVZEUjoZJCPWRAqw= Bytes: 2715 Bill Sloman wrote: > The problem is that you choose the mode when you choose the diode. Your > formulation suggests that you think somebody could to operate one diode > in one mode or the other. Only a hopeless newbie could think that, but > some of the lurkers aren't all that sophisticated, and a few of our > posters aren't much better. > > Gerhard Hoffmann has pointed out that even a 4.7V zener diode has enough > avalanche component in it's breakdown mechanism to introduce lots of > noise though the temperature coefficient of the reverse voltage is still > marginally negative. Thank you for taking the time to clear things up. It's time to move on to a another interesting (from my own perspective) topic. At least one person refers to this Shockley pn junction equation as "famous": VBE = VT*ln(IE/IS) It makes me feel like a hopeless newbie for such a well known equation to remain unknown to me until relatively recently. My curiosity moved me to peek at the 12.5 THE THEORY OF A p-n JUNCTION section of ELECTRONS AND HOLES IN SEMICONDUCTORS by Shockley. So far, nothing recognizably resembling the above equation jumps out at me from the Shockley. Fortunately, "success has many fathers." So this paper (credits Widlar's work) will suffice: Danke, -- Don, KB7RPU, https://www.qsl.net/kb7rpu There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.