? 2011 microchip technology inc. ds51342b total endurance? v5.00 quick start guide
ds51342b-page 2 ? 2011 microchip technology inc. information contained in this publication regarding device applications and the like is provided only for your convenience and may be superseded by updates. it is your responsibility to ensure that your application meets with your specifications. microchip makes no representations or warranties of any kind whether express or implied, written or oral, statutory or otherwise, related to the information, including but not limited to its condition, quality, performance, merchantability or fitness for purpose . microchip disclaims all liability arising from this information and its use. use of microchip devices in life support and/or safety applications is entirely at the buyer?s risk, and the buyer agrees to defend, indemnify and hold harmless microchip from any and all damages, claims, suits, or expenses resulting from such use. no licenses are conveyed, implicitly or otherwise, under any microchip intellectual property rights. trademarks the microchip name and logo, the microchip logo, dspic, k ee l oq , k ee l oq logo, mplab, pic, picmicro, picstart, pic 32 logo, rfpic and uni/o are registered trademarks of microchip technology incorporated in the u.s.a. and other countries. filterlab, hampshire, hi-tech c, linear active thermistor, mxdev, mxlab, seeval and the embedded control solutions company are registered trademarks of microchip technology incorporated in the u.s.a. analog-for-the-digital age, appl ication maestro, codeguard, dspicdem, dspicdem.net, dspicworks, dsspeak, ecan, economonitor, fansense, hi-tide, in-circuit serial programming, icsp, mindi, miwi, mpasm, mplab certified logo, mplib, mplink, mtouch, omniscient code generation, picc, picc-18, picdem, picdem.net, pickit, pictail, real ice, rflab, select mode, total endurance, tsharc, uniwindriver, wiperlock and zena are trademarks of microchip tec hnology incorporated in the u.s.a. and other countries. sqtp is a service mark of microchip technology incorporated in the u.s.a. all other trademarks mentioned herein are property of their respective companies. ? 2011, microchip technology incorporated, printed in the u.s.a., all rights reserved. printed on recycled paper. isbn: 978-1-61341-131-5 note the following details of the code protection feature on microchip devices: ? microchip products meet the specification cont ained in their particular microchip data sheet. ? microchip believes that its family of products is one of the mo st secure families of its kind on the market today, when used i n the intended manner and under normal conditions. ? there are dishonest and possibly illegal methods used to breach the code protection feature. all of these methods, to our knowledge, require using the microchip produc ts in a manner outside the operating specifications contained in microchip?s data sheets. most likely, the person doing so is engaged in theft of intellectual property. ? microchip is willing to work with the customer who is concerned about the integrity of their code. ? neither microchip nor any other semiconductor manufacturer c an guarantee the security of their code. code protection does not mean that we are guaranteeing the product as ?unbreakable.? code protection is constantly evolving. we at microchip are co mmitted to continuously improvi ng the code protection features of our products. attempts to break microchip?s c ode protection feature may be a violation of the digital millennium copyright act. if such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that act. microchip received iso/ts-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in chandler and tempe, arizona; gresham, oregon and design centers in california and india. the company?s quality system processes and procedures are for its pic ? mcus and dspic ? dscs, k ee l oq ? code hopping devices, serial eeproms, microperipherals, nonvolatile memory and analog products. in addition, microchip?s quality system for the design and manufacture of development systems is iso 9001:2000 certified.
? 2011 microchip technology inc. ds51342b-page 3 total endurance? quick start guide total endurance? v5.00 quick start guide introduction total endurance software is a simple-to-use, yet powerful, software tool to help system designers determine the endurance of microchip eeproms in a given application. the software will calculate the expected endurance based on the conditions entered by the user. installing the software you can find total endurance v5.00 on microchip?s web site, www.microchip.com . when you have downloaded total endurance v5.00 install.exe, simply launch the setup file and follow the instructions. using total endurance there are four main parts of the screen: (see screen sample) options the options area allows you to choose whether or not you want to calculate endurance up to a specific period of time (?application life?) or if you want the total endurance soft- ware to calculate how long it will take to get to a specific failure rate (ppm). if it takes longer than 41 years to get to the failure rate you have specified, then the program will calculate out to 41 years and then display the actual failure rate at that time. you can also select the x-axis display of the graph ? either ?cycles? or ?time?. endurance parameters here the parameters are entered that the total endurance software will use to calculate the expected failure rate. select the device you want using the ?product family? and ?device selection? drop-down menus. next, select the operating voltage of your application (the v dd supply level of the eeprom), and the ambient temperature of the application (temperature has a strong effect on endurance). depending on what you selected in options, you can enter the application life (or ppm level) you need the total endurance software to calculate. select the string length (number of bytes being written during the write command, use 1 for byte writes). and finally, the number of times those bytes are written per day. numerical results this area provides the results of your calculation in numerical form. it shows the failure rate in fits (failure in time) and ppm (parts per million), calculates the mtbf (mean time between failure), gives the life of the application (calculated if you have asked total endurance software to calculate up to a certain ppm failure rate), and calculates the number of write cycles you are performing over the life of your application.
total endurance? quick start guide ds51342b-page 4 ? 2011 microchip technology inc. graphic results this shows the failure rate over time (or cycles) up to the lifetime (calculated or entered) of the application. the enlarge button displays a full-screen version of the graph. failure rate over time architecture microchip employs two different array architectures in its eeprom devices. the differ- ence between the two involves what happens during the write cycle when less than a full page is written. to the end user, this change does not affect communication; it only affects how endurance is specified. byte architecture microchip?s old eeprom architecture was a byte architecture that allowed the user to do a true byte write where only the byte(s) being addressed were modified during the write cycle. the number of bytes being programmed in this architecture could be anywhere from one single byte to an entire page.
? 2011 microchip technology inc. ds51342b-page 5 total endurance? quick start guide page architecture microchip?s new eeprom architecture is page based and forces the entire page to undergo a write cycle even when individual bytes are addressed. this design supports pseudo byte writes (or multiple bytes of less than a full page) so the new devices can be used as a replacement for older devices with no code changes required. all writes to a page now refresh all of the bytes of the page whether the specific bytes are addressed or not. with the new page architecture, the entire page is read into latches at the beginning of the write command. as data is received, it is loaded into the appropriate latches to replace the old data. at the end of the write command, the entire page is written using the data in the latches. this is essentially a read-modify-write operation on the entire page. because the entire page endures a write cycle during each write operation, endurance is specified per page. how does this affect me? most applications should not encounter any issues when moving between these two architectures due to the high endurance of microchip eeprom technology. microchip recommends that byte writes be minimized, and for the mcu to buffer the data and performs either a whole page write, or writes as many bytes in one write com- mand as possible. a side benefit of performing a page write vs. a multiple of individual byte writes is a reduction in average power consumption; also the total system write time is reduced by doing fewer total writes. an1028, ? recommended usage of microchip i 2 c? serial eeprom devices, ? covers a number of examples showing the code efficiencies and reduction in time taken between writing individual bytes vs. an entire page. the data below was collected on actual microchip devices. it shows that the endurance is very high for microchip serial eeproms and that most users should not have any endurance concerns.
total endurance? quick start guide ds51342b-page 6 ? 2011 microchip technology inc. notes:
? 2011 microchip technology inc. ds51342b-page 7 total endurance? quick start guide notes:
ds51342b-page 8 ? 2011 microchip technology inc. americas corporate office 2355 west chandler blvd. chandler, az 85224-6199 tel: 480-792-7200 fax: 480-792-7277 technical support: http://www.microchip.com/ support web address: www.microchip.com atlanta duluth, ga tel: 678-957-9614 fax: 678-957-1455 boston westborough, ma tel: 774-760-0087 fax: 774-760-0088 chicago itasca, il tel: 630-285-0071 fax: 630-285-0075 cleveland independence, oh tel: 216-447-0464 fax: 216-447-0643 dallas addison, tx tel: 972-818-7423 fax: 972-818-2924 detroit farmington hills, mi tel: 248-538-2250 fax: 248-538-2260 indianapolis noblesville, in tel: 317-773-8323 fax: 317-773-5453 los angeles mission viejo, ca tel: 949-462-9523 fax: 949-462-9608 santa clara santa clara, ca tel: 408-961-6444 fax: 408-961-6445 toronto mississauga, ontario, canada tel: 905-673-0699 fax: 905-673-6509 asia/pacific asia pacific office suites 3707-14, 37th floor tower 6, the gateway harbour city, kowloon hong kong tel: 852-2401-1200 fax: 852-2401-3431 australia - sydney tel: 61-2-9868-6733 fax: 61-2-9868-6755 china - beijing tel: 86-10-8569-7000 fax: 86-10-8528-2104 china - chengdu tel: 86-28-8665-5511 fax: 86-28-8665-7889 china - chongqing tel: 86-23-8980-9588 fax: 86-23-8980-9500 china - hangzhou tel: 86-571-2819-3180 fax: 86-571-2819-3189 china - hong kong sar tel: 852-2401-1200 fax: 852-2401-3431 china - nanjing tel: 86-25-8473-2460 fax: 86-25-8473-2470 china - qingdao tel: 86-532-8502-7355 fax: 86-532-8502-7205 china - shanghai tel: 86-21-5407-5533 fax: 86-21-5407-5066 china - shenyang tel: 86-24-2334-2829 fax: 86-24-2334-2393 china - shenzhen tel: 86-755-8203-2660 fax: 86-755-8203-1760 china - wuhan tel: 86-27-5980-5300 fax: 86-27-5980-5118 china - xian tel: 86-29-8833-7252 fax: 86-29-8833-7256 china - xiamen tel: 86-592-2388138 fax: 86-592-2388130 china - zhuhai tel: 86-756-3210040 fax: 86-756-3210049 asia/pacific india - bangalore tel: 91-80-3090-4444 fax: 91-80-3090-4123 india - new delhi tel: 91-11-4160-8631 fax: 91-11-4160-8632 india - pune tel: 91-20-2566-1512 fax: 91-20-2566-1513 japan - yokohama tel: 81-45-471- 6166 fax: 81-45-471-6122 korea - daegu tel: 82-53-744-4301 fax: 82-53-744-4302 korea - seoul tel: 82-2-554-7200 fax: 82-2-558-5932 or 82-2-558-5934 malaysia - kuala lumpur tel: 60-3-6201-9857 fax: 60-3-6201-9859 malaysia - penang tel: 60-4-227-8870 fax: 60-4-227-4068 philippines - manila tel: 63-2-634-9065 fax: 63-2-634-9069 singapore tel: 65-6334-8870 fax: 65-6334-8850 taiwan - hsin chu tel: 886-3-6578-300 fax: 886-3-6578-370 taiwan - kaohsiung tel: 886-7-213-7830 fax: 886-7-330-9305 taiwan - taipei tel: 886-2-2500-6610 fax: 886-2-2508-0102 thailand - bangkok tel: 66-2-694-1351 fax: 66-2-694-1350 europe austria - wels tel: 43-7242-2244-39 fax: 43-7242-2244-393 denmark - copenhagen tel: 45-4450-2828 fax: 45-4485-2829 france - paris tel: 33-1-69-53-63-20 fax: 33-1-69-30-90-79 germany - munich tel: 49-89-627-144-0 fax: 49-89-627-144-44 italy - milan tel: 39-0331-742611 fax: 39-0331-466781 netherlands - drunen tel: 31-416-690399 fax: 31-416-690340 spain - madrid tel: 34-91-708-08-90 fax: 34-91-708-08-91 uk - wokingham tel: 44-118-921-5869 fax: 44-118-921-5820 worldwide sales and service 05/02/11
|
