Content originally posted in LPCWare by probatista on Thu Mar 13 06:27:39 MST 2014 Both the LPC175x and LPC176x errata sheets report an issue with RTC reliability: "The Real Time Clock (RTC) does not work reliably within the temperature specification".
1. Since this issue is said to affect only revisions "Rev A" and "-", I want to buy a newer revision. The Errata sheet explains how to read the revision from the top marking, but I'll buy it on the internet and therefore will not be able to read it. How can I know which revision is the device I will buy without reading its top marking? Does the 551 on this manufacturer part number "LPC1756FBD80,551" says something about it? I'm thinking about buying this: http://br.mouser.com/ProductDetail/NXP/LPC1756FBD80551/?qs=%2fha2pyFaduifPp1Rdf3p9P0nsUa%252bPB82arX...
2. Are there any more details about this issue? Problems only occur on extreme temperatures (next to the device limits)? If my application will only operate from 10 to 40 degC should I expect any problem? This issue will only cause small delays or might even stop the RTC?
Content originally posted in LPCWare by probatista on Sun Mar 16 16:12:59 MST 2014 Indeed, just checked now, I hadn't noticed Table 2 distinguishing which issues applies to which version. Thanks for the info!
Content originally posted in LPCWare by mc on Fri Mar 14 20:41:25 MST 2014 Hi Paulo, Yes, the issue has been fixed in RevA version onward. Please see errata link below. http://www.nxp.com/documents/errata_sheet/ES_LPC176X.pdf
Content originally posted in LPCWare by cfb on Fri Mar 14 16:27:47 MST 2014 Quote: probatista Since this issue is said to affect only revisions "Rev A" and "-" In the errata Dated Sep 2013 this issue is stated only to affect revision "-" which precedes Rev A. I understood that the problem was fixed about three years ago in Rev A.
Content originally posted in LPCWare by probatista on Fri Mar 14 04:47:55 MST 2014 I asked NXP using the form on their site about my question 1, just got their answer:
Quote: There is currently no newer version than revision A.