Dallas DS1287 & DS12887 RTC & other DS RTC Chip Repairs
ฝัง
- เผยแพร่เมื่อ 3 ต.ค. 2024
- For other Dallas DS chips not in this video: See Update on the bottom of the comments.
Description: The Dallas DS1287 RTC (Real Time Clock) has an internal battery that over time goes bad. Even the NEW ones since they're still NOS (New Old Stock) either won't work long or won't work at all, as the battery life is only supposed to last 10 years.
A friend of has on old PS2 that won't boot up so, he asked me to install a new backup batter to fix his. This video is how I did the procedure.
Before we begin here's a really good PDF that has some great options on Re-Powering or replacing them with a more up to date chip that doesn't require batteries. worldphaco.com/...
Here's the data sheet for the if you'd like to see how it works DS1387: www.datasheeta...
ITEMS YOU'LL NEED:
1. 3 - 4" OF WIRE, 20AWG OR CLOSE TO IT.
2. Solder.
3. Soldering Iron.
4. Liquid RMA Flux, ie. KESTER 186
5. 90% OR Higher Isopropyl Alcohol to clean solder joints.
6. Acid Brush with 2/3rds top cut off to clean solder joints.
7. Dremel or Rotary Tool of some kind. Harbor Freight comes to mind.
8. Carbide Grinding Tip MED/SMALL for the Rotary Tool.
9. Coin Battery Button Holder Socket.
10. Optional: 1/8" Heat Shrink about 1/4" long any color.
Let's Begin.
UPDATE Procedure for other DS Chips.
1. CAREFULLY; Grind through the epoxy above ALL the pins to find the battery connections.
2. Connect a digital meter to the pins that have a wire attached to find the polarity, that's if it still has some charge left over, most won't.
3. If it has a charge left over, take note of the positive and negative pins!!!
4. If the old battery doesn't have a charge or if the polarity can't be determined with a meter; then gently grind away the sides until you can get the top off.
5. Grind the away the epoxy to expose the battery and hope the polarity is marked on the battery.
6. If the polarity is not marked on the battery but it has a part number on it, you can look up the battery polarity on line.
7. If the polarity or part number is not marked, you're pretty much done for now. Check the forums, or post a question on a forum to find a solution. Or you can purchase a used on on line and try again.
8. Once you have the battery to pin connections and the polarity connect a backup battery as shown in the later part of the video above.
I hope this helps you in your project.
*** Personally I would take the time to use a Dremel and cut away the epoxy & find the pin connections and the polarity on battery.
You have nothing to loose anyways since it's already a dead chip.
** If the video helped please take the time to give me a thumbs up for the work I put into it. Best Wishes n Blessings Keith Noneya - แนวปฏิบัติและการใช้ชีวิต
This was very useful information. Thank you for taking the time to put this video together and share it!
You're welcome bud, glad to help out. Best Wishes & Blessings. Keith Noneya
Just got mine fixed and now I have a fully functional 25mhz 486sx with a 5.25 inch floppy running windows 3.11. Thank you for explaining how to do this so well.
Thanks James glad it helped. Best Wishes & Blessings. Keith Noneya
GOD BLESS that man who made this video!
Перевод Google: Добро пожаловать, сэр. Спасибо за благословение. Пусть мой Господь и Бог благословит вас и вашу семью тоже. Кейт Нонейя
Google Translation: You're welcome sir. Thank you for the blessing. May my Lord and God bless you and your family too. Keith Noneya
Great job!!!! today is August 6 2024 from Spain
Thanks, I hope it worked good for you. Best Wishes & Blessings. Keith Noneya
Thank you very much, you just saved another one industrial pc that works in production. In additional, you can use plc battery 14250, so you don't need to replace it next 15 years at least.
Владимир, пожалуйста. Рад помочь людям работать. Пришлите мне фотографию с оборудованием.
Лучшие пожелания и благословения. Keith
Vladimir you are welcome. Glad to help keep people working. Send me a picture of you with the equipment.
Best Wishes and Blessings. Keith
Thanks for doing this. Solved a big problem for us and General Motors.
Always glad to help. Keep them GM's coming. I'll take a Cadillac SUV, LOL. Best Wishes & Blessings. Keith Noneya
GM... sounds like they are using KUKA KRC1??
Note that these are now available NEW (fresh battery) from Mouser or Digikey. Of course you will need to load the program into the new one. When you see the price, get ready to say, "ouch!"
Wow thanks for the info! Do you have a link to the product I can put in the video description?
This is EXACTLY! what i was looking for! Thanks for saving my old ASUS P/I P55T2P4.
Wooo Hooo another computer saved and put back into service. Thanks for taking the time to thank me. Best Wishes & Blessings. Keith Noneya
I like how cleanly you removed the epoxy from pin 16. I have a Dremel tool (well, Harbor Freight knock off) I'm going to give this a shot tomorrow.
Hey Shawn let us know how it went. Best Wishes and Blessings. Keith Noneya
@@keithnoneya It went well. Thanks. I have 4 DS1287's and 1 '286 motherboard. So, I had a RTC to experiment with. I hacked one up and totally removed the BR1225. It gave me insight how things were connected. I know of the website that shows it, but I wanted to see it for myself. The datecode is from 1989 and battery voltage is 155 mV. On the next next one, the datecode was from 1990. I made the real mod and exposed the battery pins. I measured 3.3 volts! I couldn't believe it. I disconnected it anyway since I'd probably install it and it would fail a week later. ;) Anyway, thanks for the video.
@@shawnerz98 Hey Shawn try this link you may find it useful. worldphaco.com/uploads/TEKTRONIX_2465b_OSCILLOSCOPE_CALIBRATION___REPOWERING_THE_DS1225.pdf Best Wishes & Blessings. Keith Noneya
Good job, saved 2 old Pentium 1 Mainboards.
Thanks I'm glad the mod worked. Don't forget to check the links in the description. One of them is how to replace it with a chip that doesn't require a battery. Best Wishes & Blessings. Keith Noneya
Perfect instructions, mine was 12887A pin 16 a little deeper than your case. But worked fine :)
Glad it worked for you David. So what does yours go in?
Keith Noneya, good ol’ 486DX100 power house :) failed to boot after battery went flat, now fine !!! :)
Wow, I used to use an old 486DX when I was in the Navy years ago. Used the old WordStar word processing program and some old EXCELL type program, don't remember what it was. You almost had to be a programmer to use them because you had to insert commands in the lines you were typing. Ah today it's all automatic just set it and go. LOL
Keith Noneya :) lotus123?
I have the same chip. Was yours soldered onto the board?
Can confirm this also works for the ODIN 1287 clone chips.
Sorry I can't, as I have not done one. Most clones have the same pin-outs so it should. If it's bad you don't have anything to loose trying. Let us know if you do and how it turns out. Best Wishes n Blessings. Keith
Already done. It's remembering the CMOS data for a Full Yes 82430i mobo with a Pentium-75 OCed to 90Mhz, 16MB RAM, 3dfx Voodoo!
The only major difference with this Odin chip is that you have to cut far deeper to get to the hidden pins. I just cheated and melted the plastic with a soldering iron.
Thanks! Just fixed my caf superlight 386sx 8 -)
You're welcome. Glad it helped. Best Wishes & Blessings. Keith Noenya
Why did you cut the top from bottom on PIN 16? Is it to avoid fast drain of the replacement battery? Thanks for this very detailed video !
Sorry for the late reply, my dad had passed away and I've been busy dealing with his estate. Yes the internal battery is bad and it could weaken or possibly short or the new battery and damage it. Good attention to detail and a great question. Thanks for watching. Best Wishes & Blessings. Keith Noneya
@@keithnoneya my condolences. Thanks for your confirmation.
thank you, i cant wait to play some dune 2 and some quake again!
Yeah I get there to sometimes. I have a friend who's into retro computers, stereos, and sound equipment. His name is Shaun. Here's a link to his channel, called SIMPLETHINGS, Good guy. th-cam.com/channels/LxoVzIzuIN1tQ7DRO7gB6g.html Thanks for watching. Best Wishes n Blessings. Keith Noneya
Thanks man! I'll check him out, I'm guessing that was his dead ps/2!
My hero :) thanks a lot!!!!! it's the same with oec12c887a
You're welcome Gibran. Thanks for the comment. Best Wishes n Blessings. Keith Noneya
Excellent work
Thank you Nadeem. Thanks for watching. Best Wishes & Blessings. Keith Noneya
Thank you! Also works it a DS1288
That good to know. What are you using it on? thanks for the info and watching. Best Wishes & Blessings. Keith Noneya
Couldnt You just solder battery to the corresponding legs on the back of the motherboard?
I mean without desoldering the rtc.
No because the pins on the chip are bent up and don't go into the motherboard. So that's why you have to grind away the side of the IC to expose them to connect the battery to where the dead battery is attached inside the IC. You don't have to disconnect the internal battery by grinding the leg in two, but if you don't the external battery won't last as long. Hope that answers your question. Best Wishes & Blessings. Keith Noneya
Does the DS1387 have the same solder points as the DS1287? I have some EISA board which needs a revive.
Hi Aerobix, According to the data sheets it certainly looks like it. You can check out the data sheet here: www.datasheetarchive.com/pdf/download.php?id=06a352d62e54c7c83effdc5190f3e441e4272f&type=M&term=DS1387 Of course since I haven't done a 1387 I can't say for sure, however most manufactures don't like to change the pinouts from model to model provided it's the same type of chip. Check out this page where they say it is: www.mcamafia.de/mcapage0/dsrework.htm So it's probably worth the try. After all it's already broken what do you have to loose? Thanks for watching and I hope that helps. Best Wishes & Blessings. Keith Noneya
You are the best... PRO
Thanks Lois I appreciate the thanks. Best Wishes & Blessings. Keith
Thank you man, you saved my life
You're welcome Chamas. What did you fix?
Thanks to you my deskpro 286e of 1989 is now functining again!
I used an old 286 back in the 80's at work. I still remember the old flat floppies we used. You should do a video on it running and doing some work or playing an old video game like Doom on it. That would really be cool. Anyways don't want to waste anymore of your time. Thanks for watching and glad it helped. Best Wishes n Blessings. Keith Noneya
hahahaha no probls bro, now it is runnig the DOS system and my next step is to put some cool games on it ! thank you a lot : )
Contact Saun at "SimpleThings". he's a friend of mine who's into old classics like your 286. He's pretty cool and goes the Make Fair here in New Orleans when it's in town. He'll have some good ideas for you and may even have some software for you or know where you can get some cheap. Here's a link to his page. th-cam.com/channels/LxoVzIzuIN1tQ7DRO7gB6g.html Tell him Keith Noneya sent you, he'll know who it is. Best Wishes n Blessings. Keith Noneya
Hi Keith, great video. I am about to attempt this myself for a Charmilles Robofil 290 wire EDM. Could you please let me know what battery did you use? CR2032?
Actually I don't remember, but any cpu button battery will do. Best Wishes & Blessings. Keith Noneya
yes and then solder drips onto the board and it's all over....
very good also works on dallas 12887A
That's good to know I amended the title to include the information. Best Wishes & Blessings. Keith Noneya
@@keithnoneya thanks mate
Hi. Nice work! I Wonder if you know where can i find any information about the internals of a DS1230Y-100. I recently begun to decap my IC, it would be nice to know the internals beforehand. Thanks!
Vladimir, I know this may sound silly, but try the datasheet here: www.datasheetarchive.com/pdf/download.php?id=279042bc26bf4f4f76a9e0a5fb0a164364ba1b&type=M&term=DS1230Y100
Here's a reply I gave to Hector Serrato below, that may help you.
"Hector;
I don't know. I looked up the data sheet and see if you can find it there by comparing it to other types buy I was unable to come to any conclusion. Here's the link for the related data sheets. Scroll down a where you see the data sheet pdf's on the right side of the page. Here's the link. www.datasheetarchive.com/DS1230Y-70-datasheet.html
Take note that there are several versions of it. You could cut the top off if it's a DIP package and grind through the case above the pins to find the battery connections. Then grind the epoxy away until you find the battery. Carefully grind the epoxy away to find the batter terminal side. Then connect a meter to the battery to find the polarity, that's if it still has some charge. If not you'll have to gently grind away all the epoxy to remove the battery in hopes they have marked the polarity on the battery itself. Either way its a delicate job. If it's a DIP socket and you know it's bad, and don't want to do the work, send it to me and i'll rip it apart and find the pins for you just for fun. Best Wishes n Blessings Keith" Also some epoxy's are sensitive to heat and you can warm it up with a hot air gun and peel it back. Hope this helps. Keith Noneya
Please help me with dallas DS1225AB-150IND
can i replace this dallas without reprogramming the new dallas?
too can i replace this dallas by DS1225AD-150?
HI Waleed, To answer your 1st question. It really depends on the circuit it's used in. If it's just for storage of the last setting of the equipment it's installed in then yes you can. If it's used to store something more important like calibration constants, then it gets a little more involved if you want to save those constants. If you don't save them your equipment will be out of calibration. If you have the equipment to calibrate the equipment then it shouldn't matter because the new constants should take the place of the old ones. In that case put a blank one in and calibrate the equipment. Hold onto the old one in case it has a hidden sub program you may need. The only other consideration is if it's used to store the program for say a Micro controller like a 8051 or one of its variants. If that's the case then certainly you'll want to save the data and transfer it to a known chip. If you don't transfer it then when you turn the equipment on it will just power up and do nothing.
To answer your 2nd question, if you look at your data sheet it will tell you if it's compatible. Note that the letter or numbers on the end usually denote the size, speed, temp and package of the chip. The size is usually in megabytes or speed in Nano Seconds and the rest will need a chart to tell you what the rest means. Check the data sheet to see how the pins are laid out. So even if the 1st part of the part number is the same and internally identical the physical size, shape and operating voltages may not be compatible. Always check the equipment operating requirements/conditions and check data sheets when installing alternate part numbers to ensure it will operate under those conditions.
I looked at the data sheet and they do look compatible except for temperature operating conditions. Look at the Data sheet here: www.datasheetarchive.com/pdf/download.php?id=6e9b9ebad636e411870c6f4d61430d302732fe&type=M&term=DS1225AB150IND and go to page 9. You'll see the part number breakdown. The only difference I can see is the temperature the chip can handle. The IND can function between -40C to 85C in degrees. The unmarked can operate from 0C to 70C in degrees. If it's in a critical environment application then make sure the environment is within the 0C to 70C or you can't use it and expect it to operate correctly. Hope that helps point you in the right direction. Best Wishes & Blessings. Keith Noneya
@@keithnoneya
Thank you very much for your wonderful explanation.
I meant what is the difference between DS1225AB and DS1225AD..
It is mentioned in the datasheet the following:
((DATA RETENTION MODE
The DS1225AB provides full functional capability for VCC greater than 4.75 volts and write protects by
4.5 volts. The DS1225AD provides full-functional capability for VCC greater than 4.5 volts and write
protects by 4.25 volts. Data is maintained in the absence of VCC without any additional support circuitry.
The nonvolatile static RAMs constantly monitor VCC. Should the supply voltage decay, the NV SRAMs
automatically write protect themselves, all inputs become “don’t care,” and all outputs become high-
impedance. As VCC falls below approximately 3.0 volts, the power switching circuit connects the lithium
energy source to RAM to retain data. During power-up, when VCC rises above approximately 3.0 volts,
the power switching circuit connects external VCC to RAM and disconnects the lithium energy source.
Normal RAM operation can resume after VCC exceeds 4.75 volts for the DS1225AB and 4.5 volts for the
DS1225AD))..
But I didn't understand anything after reading.
Is it possible to exchange between them?
@@waleedattia7014 It appears you can exchange them, with the exception of the basic is only 10% accurate, in timing, and the IND is 5% accurate. The only other changes I saw was the operating temperatures. Both those differences are listed on pg. 9. If the equipment you're installing them in is withing those parameters then you should be able to use either in the equipment. Just out of curiosity what is it going to be installed in? Best Wishes & Blessings. Keith Noneya
Hi, I have a DS12C887 RTC, Can I use this Tutorial in my case??? Please, answer soon. Thanks
Lorena, I'm not sure, this is the only one I've done it to. This question gets asked quite often, as there are a lot of RTC's out there made by Dallas. The best I can offer is do the research on the pin-outs using the Data Sheet. Also you can cut the top off and gently grind down the epoxy inside until you can find the battery leads, test them for which one is negative and then do the procedure in the video. You should also read the comments on the video to get a good idea of what others are doing to fix this problem. Wish I could help more, but this is my best suggestion that I think will work. Thanks for watching. Best Wishes & Blessings. Keith Noneya
What I see happening is the embedded pins 16 (ground) and 20 (battery positive) are exposed by cutting away body molding, then #16 is severed, then soldering to the ground pin portion that is connected to the circuitry and not the old battery. I have a DS12887A and all pins do extend out of the body. Should I sever both pins and solder to the portion that protrudes out of the molded chip body?
The chip is seated in a socket when assembled onto the board. (I am not an electronics wiz but can do intricate work).
Hey DDB try this link. I think it will give you a pretty good perspective on your options. It's a PDF by a Dr. who has done some extensive study and experiments on either re-powering these chips or replacing them with some modern versions that don't require batteries. Here's the PDF link:
worldphaco.com/uploads/TEKTRONIX_2465b_OSCILLOSCOPE_CALIBRATION___REPOWERING_THE_DS1225.pdf
Hope this points you in the right direction. Best Wishes and Blessings. Keith Noneya
How bought a Dallas DS1742W-150 Timekeeping Ram?
How do you buy one or you bought one, not sure what you're comment is saying. Let me know if you have a question. Keith Noneya PS the three dots on the right of your comment allow you to edit your comment. Keith
Works with DS1643??
I really couldn't say for sure. You'll have to compare the pinouts in the data sheets to make sure. Also you can check out this great article for some more information on how they work here: worldphaco.com/uploads/TEKTRONIX_2465b_OSCILLOSCOPE_CALIBRATION___REPOWERING_THE_DS1225.pdf Hope that points you in the right direction. Best Wishes & Blessings. Keith Noneya
how to remove the chip from the board? do i need to desolder?
+JohanTwinsen Sorry I haven't checked my email in a few days. It's best to remove the chip from the board to ensure that all the particles don't contaminate the board. You'll need a really steady hand to do this and a vice to hold the chip still while you Dremel out the chip to gain access to the internal connections. Hope this answers your question. Feel free to ask more anytime. Best Wishes n Blessings Keith
hi you know what pin is negative and positve but in DALLAS DS1230Y ???
I don't know. I looked up the data sheet and see if you can find it there by comparing it to other types buy I was unable to come to any conclusion. Here's the link for the related data sheets. Scroll down a where you see the data sheet pdf's on the right side of the page. Here's the link. www.datasheetarchive.com/DS1230Y-70-datasheet.html
Take note that there are several versions of it. You could cit the top off if it's a DIP package and grind through the case above the pins to find the battery connections. Then grind the epoxy away until you find the battery. Carefully grind the epoxy away to find the batter terminal side. Then connect a meter to the battery to find the polarity, that's if it still has some charge. If not you'll have to gently grind away all the epoxy to remove the battery in hopes they have marked the polarity on the battery itself. Either way its a delicate job. If it's a DIP socket and you know it's bad, and don't want to do the work, send it to me and i'll rip it apart and find the pins for you just for fun. Best Wishes n Blessings Keith
thanks very much.
I buy 3 pieces for try first that original.
thanks again
Will this replace a ds12887A?
You'll have to look up the data sheets on both and compare the pin outs, memory and voltages, but I think it will if the pin outs are the same.
@keithnoneya in the A variant, pin 21 (DIP) is an active low general purpose RAM clearing function.
Dear Keith,
I'm wondering, if do you know what type of battery is inside in chip? What is weight of lithium there? Unfortunately I can't find this data anywhere(
Sorry I don't know what the battery is, other than it's a 3V Lithium battery. I suppose if you really wanted to know you could excavate the whole top off and then pull the battery and look at the number, IF the manufacture used a battery that has a number. Let us know if you do find out. Best Wishes n Blessings. Keith Noneya
I found it after very deep searching in the internet. For this chip Dallas used Panasonic's coin battery BR1225. There are more information here www.maximintegrated.com/content/dam/files/design/qa-reliability/ul-recognition/E141114-Vol-2-Sec-1-Conditions-of-Acceptability.pdf
Sorry I didn't see the replay until today.
That's a pretty good find. I'm not sure on the battery as I looked up the specs for it and the diameter of the BR1225 is 12mm or .472 inches, that's a little big for a microchip, so they must be talking about a circuit board or something. I do know they make smaller Lithium batteries for hearing aids or the like so maybe it's a smaller version of it. So what is your chip being used in! Keith
i'm not sure, but it looks like DS1287 has 24-pin DIP package, which should have .685 inches width, what should be enough to fit .472 inches button battery. It is just guess, I operated only datasheets, didn't measured it manually.
@@IvanLutsV I have 4 DS1287's. I sacrificed one of them to cut it up and see what battery was used. Yup, just like yo said, BR1225. :)
Very good
Glad you like the video. Thanks for watching. Best Wishes and Blessings. Keith Noneya
I am searching this after finding two of these chip things in an electronics repair kit . They are new . Any advice on how I could use these or if their is a demand for them ? They read this on front first there is a white clock . And it reads " DALLAS DS1287 REAL TIME 9123B3 013673 . And on the back it reads PHILIPPINES 427AA . I appreciate any info you may be able to help me with . Thank You and God Bless . Are these things batteries ? Apologize if that sounds like a stupid question .
No problem at all. They are real time clocks that provide time in the following format: Seconds, Minutes, Hours, Day, Day of the week, Date, Month, Year & Leap Year compensation. The data is maintained with a built in battery. The problem is the internal battery over time degrades and fails depending on manufacture date. From the date of manufacture they are supposed to last 10 years, most last past that depending on the environment they are in. Even if the part is a NOS (New Old Stock) it can not be trusted as they are probably old and will fail soon. I'm not familiar with date codes on the chips, but I suspect the "PHILIPPINES 427AA" is the country of manufacture and lott and possible date code. You can look up the data sheet here: www.datasheetarchive.com/dl/507a40edf8db7ebea38a829250c14d72fee6cf/O/ds1287 For the answers to your other questions I would go to a forum or do a search on chip markings. Sorry I couldn't answer all your questions but I hope I gave you a good start. Try posting the question on the EEVblog Forum here: www.eevblog.com/forum/ Thanks for watching.
Best Wishes n Blessings. Keith
Does it work with Benchmarq bq3287AMT? Thank you for the tutorial.
HI Kokomal, I really don't know this was handed to me by a friend who knew the procedure and asked if I could do it for him. I gladly did it for the experience. If you find out if it does work on your chip drop us a comment. Sorry I couldn't help more. Thanks for watching. Best Wishes n Blessings. Keith Noneya.
The datasheet for the Benchmarq chip says it's directly compatible with the Dallas chip. (It's just a Chinese clone of the Dallas chip at the end of the day.) I can confirm that the procedure in the video will work with the Benchmarq chip, as I have one from an old Asus socket 7 board.
Thanks for the video .... Possible help. Is this video applicable to the DS1642
I don't think so. I looked up the data sheet for the DS1287 & your DS1642 and they have different pin names. Here's the link for the DS1287 & the DS1642.
- DS1287 www.datasheetarchive.com/pdf/download.php?id=7059617b31a7c9e2772338569eb0b2344f0e47&type=M&query=ds1287
- DS1642 www.datasheetarchive.com/pdf/download.php?id=4d58215c5e55aeb674c25b82910f23dcd5482b&type=M&query=ds1642
I would grind through the epoxy above the pins to find the battery connections. Then connect a digital meter to the battery to find the polarity, that's if it still has some charge left over. If it doesn't have a charge or if the polarity can't be determined, then you'll have to gently grind away the sides until you can get the top off. Then grind the away the epoxy to expose the battery to find the pin connection and hope the polarity is marked on the battery. Either way its a delicate job. Once you have the battery to pin connections and the polarity it's the same process shown in the video above to connect a replacement battery. I hope this helps you in your project. Personally I would take the time to use a Dremel to cut away the epoxy & find the battery. You have nothing to loose anyways since it's already a dead chip. Best Wishes n Blessings Keith
Thanks for the reply please help Mr. Keith .... I want to install the DS1642-150 battery
Hi abdo, not sure how I can help you. I think you're just going to have to get a Dremel tool and grind out the old battery and figure it out like I said in my previous post. If have a suggestion on how I can help you let me know. Best Wishes n Blessings. Keith Noneya
I've try replacing 1642 battery . the problem is how to calibrate the clock.
Hi Glen I can't help you with that one. I just know how to change the battery. The chip in the video is from a friend who asked me to do the repair for him. If you do figure it out, put a video up on your channel and drop me a link in the comment here. Thanks for watching. Best Wishes n Blessings. Keith Noneya
I am wondering if you can list the advantages to having the replaceable battery.
Cost?
Availability?
Life?
I can still find the Dallas chip and they will last 5 to 10 years but when removed I still need to send in my realtime board to have the CMOS settings reset. If a Button battery is used will it last 20 years? When the button battery is removed I will still need to send in my board for CMOS settings reset.
One of the best questions on this I've had. I can think of several advantages:
- 1. Your scope, computer or what ever you have it in, won't go down at the least opportune time. If your chip is in a piece of test equipment and your company relies on the equipment and the battery goes dead. Now you have to get another piece of test equipment or repair and re-calibrate the piece. That causes delays and possibly your company reputation.
- 2. Again if it's in a calibrated piece of equipment you'll have to get it repaired and re-calibrated.
As for the life of the button battery that depends on the current draw of the chip it's in. You can find that information in the data sheet.
- If the button battery dies it's easier to change.
- CMOS reset, that depends on what equipment the chip is in. If it has stored data, you'll need to copy it first then change the battery then reload the data onto the chip.
- If the battery is already dead then any data you had on that chip is gone.
- I found a website that answers your questions in detail but I don't remember the link. If I find it again I'll post another comment on it with the link.
Hope that helps answer some of your questions. I'll look for the link when I get home.
PS the Dallas chips you find are probably New Old Stock NOS, the batteries in those are just as old (bad) and won't last. So it's better to replace the battery with a button style or another non-volatile chip. Thanks for watching. Best Wishes and Blessings. Keith Noneya
Ok found the article I was talking about. Here's a link to the PDF.
worldphaco.com/uploads/TEKTRONIX_2465b_OSCILLOSCOPE_CALIBRATION___REPOWERING_THE_DS1225.pdf
This article should answer all your questions and then some. Hope this helps. Best Wishes & Blessings. Keith Noneya
not a DS12887!
I included the 12887 because it's pin compatible with the 1287 and should work for the 12887 per the data sheet here; datasheet.octopart.com/DS1287-Dallas-Semiconductor-datasheet-7278225.pdf I've also had people tell me it will work on the 12887 as well, so I included it so others might be able to fix there's. If you have one try it and let me know if I was told the truth. A nice video on it would help as well. Thanks for watching. Best Wishes & Blessings. Keith Noneya
Hey, that's what I need to do
infamous and ugly one this was indeed....my pi55t2p4 asus mobo was served by this and I have got to do the same job.