Post by thread:[EE:] Silly Question, what is CR

Hello all. I have a super easy question. I've been looking at a lot of scrap circuit boards kickin around here, and I always notice little parts (usually look like SMT transistors) which are silkscreen labelled CR1, CR2, etc... What does CR stand for? The only thing I can thing of is Comparator. Is that right? Thanks ahead of time. MJ Brush -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

crystal? Peter ----- Original Message ----- From: "Matthew Brush" <spam_OUTmatthewbrushTakeThisOuTYAHOO.CA> To: <.....PICLISTKILLspam@spam@MITVMA.MIT.EDU> Sent: Wednesday, June 02, 2004 6:38 AM Subject: [EE:] Silly Question, what is CR Hello all. I have a super easy question. I've been looking at a lot of scrap circuit boards kickin around here, and I always notice little parts (usually look like SMT transistors) which are silkscreen labelled CR1, CR2, etc... What does CR stand for? The only thing I can thing of is Comparator. Is that right? Thanks ahead of time. MJ Brush -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

must be a ceramic resonator Peter ----- Original Message ----- From: "Matthew Brush" <matthewbrushKILLspamYAHOO.CA> To: <.....PICLISTKILLspam.....MITVMA.MIT.EDU> Sent: Wednesday, June 02, 2004 6:38 AM Subject: [EE:] Silly Question, what is CR Hello all. I have a super easy question. I've been looking at a lot of scrap circuit boards kickin around here, and I always notice little parts (usually look like SMT transistors) which are silkscreen labelled CR1, CR2, etc... What does CR stand for? The only thing I can thing of is Comparator. Is that right? Thanks ahead of time. MJ Brush -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

MJ Brush wrote... >I have a super easy question. I've been looking at a lot >of scrap circuit boards kickin around here, and I always >notice little parts (usually look like SMT transistors) >which are silkscreen labelled CR1, CR2, etc... What does >CR stand for? The only thing I can thing of is Comparator. >Is that right? Nope. CR = "Crystal Rectifier," a term once used for diodes, but largely unused since very late in the Jurassic Age. Why it survives as a component designator abbreviation, I've never been able to figure out. I use "D" for diodes. Dave D. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

----- Original Message ----- From: "Dave Dilatush" <EraseMEdavedilatushspam_OUTTakeThisOuTCOMCAST.NET> Subject: Re: [EE:] Silly Question, what is CR > CR = "Crystal Rectifier," a term once used for diodes, but > largely unused since very late in the Jurassic Age. I knew it was a diode, but I didn't know where the CR came from. Thanks. --McD -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

pic microcontroller discussion list wrote: >> which are silkscreen labelled CR1, CR2, etc... What does >> CR stand for? > > CR = "Crystal Rectifier," a term once used for diodes, but > largely unused since very late in the Jurassic Age. > > Why it survives as a component designator abbreviation, I've > never been able to figure out. I use "D" for diodes. > I've wondered about that too. My theory is that it is meant to mean "current rectifier" -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

"Crystal Rectifier" sounds about right :) The specific ones I'm looking at right now are in that little 3pin SMT package that a lot of transistors and voltage regulators come in. I also remember seeing them labelling what I would've guessed were diodes, but assumed they weren't cuz they didn't say 'D5' or whatever. Anyway, now I know and maybe it wasn't a silly question. Thanks, Peace MJ Brush {Original Message removed}

On Wednesday, Jun 2, 2004, at 03:38 US/Pacific, Matthew Brush wrote: > I always notice little parts (usually look like SMT transistors) which > are silkscreen labelled CR1, CR2, etc... What does CR stand for? Parts labled CRn are usually rectifiers (ie diodes.) For instance, see here: www.blueguitar.org/new/text/threads/from_mark/ Voltage%20Multipliers.pdf I'm not sure what CR stands for. Perhaps "Current Rectifier" to indicate a component handling significant power (compared to a signal diode)? BillW -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Phil Eisermann wrote... >I've wondered about that too. My theory is that it is meant to >mean "current rectifier" No, it's "crystal rectifier"; just an ancient term for diode. See http://www.hyperdictionary.com/dictionary/crystal+rectifier and http://www.tpub.com/content/neets/14179/css/14179_27.htm AFAIK the term originated with the advent of germanium point-contact diodes. Dave D. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Cold Rectifier. It has no filament, like other (vacuum tube) rectifiers. Cheers, Bob > I have a super easy question. I've been looking at a lot of scrap circuit > boards kickin around here, and I always notice little parts (usually look > like SMT transistors) which are silkscreen labelled CR1, CR2, etc... What > does CR stand for? The only thing I can thing of is Comparator. Is that > right? -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

It must be on a very old schematic ----- Original Message ----- From: "Matthew Brush" <matthewbrushspam_OUTYAHOO.CA> To: <@spam@PICLISTKILLspamMITVMA.MIT.EDU> Sent: Wednesday, June 02, 2004 6:38 AM Subject: [EE:] Silly Question, what is CR Hello all. I have a super easy question. I've been looking at a lot of scrap circuit boards kickin around here, and I always notice little parts (usually look like SMT transistors) which are silkscreen labelled CR1, CR2, etc... What does CR stand for? The only thing I can thing of is Comparator. Is that right? Thanks ahead of time. MJ Brush -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.