The nearest equivalent 6.5 digit DMM of another brand that I can find is the Keithley DM6500. I originally chose the Keysight simply based on more prior experience (40+ years) with HP instruments than any other brand.We have SDM3065X in stock for around $1200 NZ if you need a meter in a hurry.
I've seen a few of the 3446x series fail with a bad main processor. They typically get hot and drag down the power supply voltage. Generally they are quite reliable though.
We've had 5 out of 12 purchased in 2019 fail the same way at work.
We've had 5 out of 12 purchased in 2019 fail the same way at work.
Mine was purchased in early 2018 so out of warranty
We've had 5 out of 12 purchased in 2019 fail the same way at work.
Likely not related to OP's fault, but something to point out (and I do hope I'm wrong here):I'm afraid you are not wrong. It is a good find though so I appreciate you taking the trouble for digging this up. There is nothing to be found on TI's website about these microcontrollers nowadays. As if they never existed!
TI/Stellaris LM3S1D21 ARM processor is discontinued 2016 and withdrawn from the market due to the flash corruption issues. The parts are a lemon, known about in 2014.
"Flash corruption or device failure may occur at power on"
"Flash memory endurance cycle specification is 100 cycles"
"Flash memory corruption may occur when device is unpowered and stored for several months - Due to the storage oxide thickness and trap-assisted electron tunneling, there are more leaked cell values than originally expected in the Flash design within several months after programming. As a result, the ECC logic is not able to repair all of the errors in the Flash memory. Data derived from customer returns predicts that devices that are left unpowered at room temperature storage for 6 months can result in failure rates of 2000-3000 DPPM per year."
Ref: TEMPEST/INFERNO LM3S Errata Document (Literature Number: SPMZ861 (https://www.ti.com/lit/er/spmz861/spmz861.pdf))
Bench multimeter product line 34461A, 34465A, 34470A use this MCU not as the main front panel processor but I think it's the Inguard processor.
If this is a real problem, silicon revisions need to be confirmed it's all 130nm parts, Keysight should be offering free extended warranty. It would be a massive debacle.
All in all these units have a ticking time bomb inside them. :palm:
Likely not related to OP's fault, but something to point out (and I do hope I'm wrong here):
TI/Stellaris LM3S1D21 ARM processor is discontinued 2016 and withdrawn from the market due to the flash corruption issues. The parts are a lemon, known about in 2014.
"Flash corruption or device failure may occur at power on"
"Flash memory endurance cycle specification is 100 cycles"
"Flash memory corruption may occur when device is unpowered and stored for several months - Due to the storage oxide thickness and trap-assisted electron tunneling, there are more leaked cell values than originally expected in the Flash design within several months after programming. As a result, the ECC logic is not able to repair all of the errors in the Flash memory. Data derived from customer returns predicts that devices that are left unpowered at room temperature storage for 6 months can result in failure rates of 2000-3000 DPPM per year."
Ref: TEMPEST/INFERNO LM3S Errata Document (Literature Number: SPMZ861 (https://www.ti.com/lit/er/spmz861/spmz861.pdf))
Bench multimeter product line 34461A, 34465A, 34470A use this MCU not as the main front panel processor but I think it's the Inguard processor.
If this is a real problem, silicon revisions need to be confirmed it's all 130nm parts, Keysight should be offering free extended warranty. It would be a massive debacle.
Front Panel processor ST SPEAr320S-2 (https://www.st.com/en/microcontrollers-microprocessors/spear320s.html) is obsolete as well, but I did not dig into its issues.
Likely not related to OP's fault, but something to point out (and I do hope I'm wrong here):
TI/Stellaris LM3S1D21 ARM processor is discontinued 2016 and withdrawn from the market due to the flash corruption issues. The parts are a lemon, known about in 2014.
"Flash corruption or device failure may occur at power on"
"Flash memory endurance cycle specification is 100 cycles"
"Flash memory corruption may occur when device is unpowered and stored for several months - Due to the storage oxide thickness and trap-assisted electron tunneling, there are more leaked cell values than originally expected in the Flash design within several months after programming. As a result, the ECC logic is not able to repair all of the errors in the Flash memory. Data derived from customer returns predicts that devices that are left unpowered at room temperature storage for 6 months can result in failure rates of 2000-3000 DPPM per year."
Ref: TEMPEST/INFERNO LM3S Errata Document (Literature Number: SPMZ861 (https://www.ti.com/lit/er/spmz861/spmz861.pdf))
Bench multimeter product line 34461A, 34465A, 34470A use this MCU not as the main front panel processor but I think it's the Inguard processor.
If this is a real problem, silicon revisions need to be confirmed it's all 130nm parts, Keysight should be offering free extended warranty. It would be a massive debacle.
Front Panel processor ST SPEAr320S-2 (https://www.st.com/en/microcontrollers-microprocessors/spear320s.html) is obsolete as well, but I did not dig into its issues.
This rings me a bell ::)
Does this means also, that the Wave Generator Trueform models 335xx & 336xx uses equal processors?
Hp
If not already mentioned in the forum, there has been issued a service note for the 34465A regarding loose front panel (date 02/02/2022 )That is a weird service note.
I have a 34465A at work, just died after maybe 40 hours. The transformer is blown (input side is open), I'm still waiting for a replacement from China. Keysight won't sell the transformer to me. This was one from only 2 we have.So it was only used for maybe 40 hours yet it's already out of warranty? Could be an open thermal fuse. But test equipment companies (Keysight, but also Keithley / Tektronix) certainly aren't as helpful with service information and spare parts as they used to be.
I had multiple Keithleys (199, 485, 2000, 6485, 6517) and never had real issues, except for some dirty contacts, blown resistors (my bad). One 6485 at work had troubles with the EEPROM, but it had at least 10 years of almost daily duty and a 199 had lost it's EEPROM after it was written about 30 years ago. I will definitely be looking for a Keithley to replace the 34465A.And I've had numerous HP/Agilent instruments, none of which has had any transformer trouble. I do have a Keithley 6485 with an open primary in its transformer. Tektronix are ignoring my requests to buy a spare, so it's just sitting there. None of this gives any useful data about the reliability of the Keysight 34465A or the Keithley DMM 6500, however. Just anecdotes.
Sad ... I just pull the trigger for Keysight 34465A, choosing between it and Fluke 8846A. Now it is too late to withdraw the order.
I just hope that the black case is not the only revision for the KS 34465A.
P.S. For those interested TME has now in stock Fluke 8846A at a good price for Europe. Though it is little outdated as display.
I have Keithley DMM 6500 from more than a year. It is better than 34356A in most respects and with 400 E cheaper!
I am buiyng KS for a "second opinion" :) as Siglent SDM 3065X is already out of calibration after 3 years.
For bench use I'd skip the Fluke 8846A and get the DMM6500 instead. Having some graphing / logging facilities on a bench DMM can be very handy at some times.
So it was only used for maybe 40 hours yet it's already out of warranty? Could be an open thermal fuse. But test equipment companies (Keysight, but also Keithley / Tektronix) certainly aren't as helpful with service information and spare parts as they used to be.
And I've had numerous HP/Agilent instruments, none of which has had any transformer trouble. I do have a Keithley 6485 with an open primary in its transformer. Tektronix are ignoring my requests to buy a spare, so it's just sitting there. None of this gives any useful data about the reliability of the Keysight 34465A or the Keithley DMM 6500, however. Just anecdotes.
It was sold about 2 or 3 years ago. I've done a lot of software for the last years, and haven't used it much.AFAIK it has 3 year warranty. Warranty status checked on the Keysight website does not matter since purchase date in a proof of sale actually matters.
I have a 34465A at work, just died after maybe 40 hours. The transformer is blown (input side is open), I'm still waiting for a replacement from China. Keysight won't sell the transformer to me.I don't think that a usual transformer is up to the task for such precision meter. It will probably inject too much leakage current into the DUT. I would take the outer insulation off and see if a thermal fuse can be reached.
I don't think that a usual transformer is up to the task for such precision meter. It will probably inject too much leakage current into the DUT. I would take the outer insulation off and see if a thermal fuse can be reached.
Siglent SDM 3065X is already out of calibration after 3 years.Which ranges ?
Siglent SDM 3065X is already out of calibration after 3 years.Which ranges ?
Are you aware of the SDM Cal site Defpom made ?
http://www.thedefpom.com/siglent_sdm_calibration.php (http://www.thedefpom.com/siglent_sdm_calibration.php)
Yes Siglent doesn't use aged references so they can drift outta spec. IIRC some owner here mapped the drift and found it almost exactly matched the LM399 datasheet drift spec.Siglent SDM 3065X is already out of calibration after 3 years.Which ranges ?
Are you aware of the SDM Cal site Defpom made ?
http://www.thedefpom.com/siglent_sdm_calibration.php (http://www.thedefpom.com/siglent_sdm_calibration.php)
Yes I am aware. But this method is useless if you don't have a calibrated source like his Datron.
I know that after one year any DMM need calibration, but the ideea was that SDM3065X left me with the sensation of not being in the same league as Keythely,Fluke or KS. This is why I headed to 34465A. But this topic make me anxious about ... :-\
If not already mentioned in the forum, there has been issued a service note for the 34465A regarding loose front panel (date 02/02/2022 )That is a weird service note.
The mounting of the front panel has not really changed in years.
If they have not made the mounting holes very large, I can not visualize how the front panel should come loose.
But then on the other hand, these 4 screws should probably have been installed since the early 34401A
Your extended warranty, is it "to" or "additional" 5 years to the standard 3 years?
I still believe that pricing wouldn't be possible if their reliability was really as dismal as it seems based on the stories of people who have had bad experiences.
I still believe that pricing wouldn't be possible if their reliability was really as dismal as it seems based on the stories of people who have had bad experiences.
Suppose the annual failure rate is 1 in 20. I would call that bad and that would be enough to generate howls of complaints, but if everyone had a contract, Keysight would have collected $820 for each failure. That should cover it, I would think. The incremental cost for an OEM to do a repair should be much less than retail.
New units come with screws mounted. The holes were left for rack mount kits, but with screws in place the face is rock solid. Without the screws it feel a little loosy.If you put the datasheets / pinout of the TM4C1292NCPDTI3 next to the LM3S1D21, you'll spot many similarities. I think TI renamed the former Luminary devices and hopefully fixed their issues in the process.
Also they seem that changed the TI MCU (TM4C1292NCPDTI3 - G4), and what that seem to be an electric switch with a jumper. (see pics)
New units come with screws mounted. The holes were left for rack mount kits, but with screws in place the face is rock solid. Without the screws it feel a little loosy.If you put the datasheets / pinout of the TM4C1292NCPDTI3 next to the LM3S1D21, you'll spot many similarities. I think TI renamed the former Luminary devices and hopefully fixed their issues in the process.
Also they seem that changed the TI MCU (TM4C1292NCPDTI3 - G4), and what that seem to be an electric switch with a jumper. (see pics)
I still believe that pricing wouldn't be possible if their reliability was really as dismal as it seems based on the stories of people who have had bad experiences.
Suppose the annual failure rate is 1 in 20. I would call that bad and that would be enough to generate howls of complaints, but if everyone had a contract, Keysight would have collected $820 for each failure. That should cover it, I would think. The incremental cost for an OEM to do a repair should be much less than retail.
I can promise you the AFR is much better than that :)
New units come with screws mounted. The holes were left for rack mount kits, but with screws in place the face is rock solid. Without the screws it feel a little loosy.
Also they seem that changed the TI MCU (TM4C1292NCPDTI3 - G4), and what that seem to be an electric switch with a jumper. (see pics)
And they used for 34465A boards marked 34460.
I wasn't able to find production date, but calibration was done in Nov.2021, so it is very likely to be in second half of 2021.
@KeithFisk: I'm sorry to hear that your unit failed do quickly I'd be curious to hear how the story ended, did Keysight offer any assistance despite the device being out of warranty. Did you repair or replace the device?
AFAIK Keysight has a policy that devices that have been stored >6 months need to be sent back to KS (at least if you bought from an official KS partner).
@Traceless: I have asked the service agent to go ahead wit the repair but have no expectation of any concession or discount on parts and labour from Keysight.
That definitely is a rework and looks like it was done by hand.Nothing about that says “rework”. It’s a later PCB version where they decided, for whatever reason, to move components to a daughterboard. Since that adds cost (both for the extra PCB, but also the labor required to connect the daughterboard), they’ll have done it for some significant reason.
I know, but that still doesn't make it okWhy it's not OK? There is nothing wrong with this. As of flux, if it's not some low leakage circuit where flux may cover unwanted gaps between the traces, other than cosmetics there is no reason to clean it. Also cleaning it is no so straightforward as it may seem. Simply cleaning it with IPA will spread the flux all around and probably under SMT components where tiny leakage current actually matters. And getting rid of so there are no visible signs of its presence will take order of magnitude more time than soldering that connection.
It's a high-end meter, not a home-made blinky; I'd expect better.You'd be surprised. But as devices become more expensive and produced in lower numbers, the amount of bodges goes up. In this case it's not even a bodge.
But apparently cleaning up flux residue is not... ::)
Glad you caught it before another transformer died!
I'd expect a primary side fuse that blows if the instrument is using 10x more current than expected. Is there none, or is it slower than the thermal fuse at this current level?
Yes, I understand; it's more practical to create a mod-board than to re-spin the main one, usually.Do you understand, though?? This isn't a mod board as such. A mod board is commonly understood to mean a daughtercard made to implement a bodge to correct an error on the main PCB, rather than making a new main PCB.
I know, but that still doesn't make it okAs wraper said, cleaning in situ could get flux residue into places it shouldn't be. And with the two boards soldered together, cleaning becomes much more difficult.
Yes, I understand; it's more practical to create a mod-board than to re-spin the main one, usually.Do you understand, though?? This isn't a mod board as such. A mod board is commonly understood to mean a daughtercard made to implement a bodge to correct an error on the main PCB, rather than making a new main PCB.
As I explained above, early versions of the board had this part of the circuit on the main PCB. Then on this later version, the main board was respun to move that part of the circuit onto a daughtercard.
This isn't a cost-saving measure, as it's more expensive in every way: the added engineering cost, a respun main PCB, a new daughtercard, and the extra labor to solder the daughtercard onto the main PCB.
I know, but that still doesn't make it okAs wraper said, cleaning in situ could get flux residue into places it shouldn't be. And with the two boards soldered together, cleaning becomes much more difficult.
So you'd be adding a cleaning step with no advantage, but plenty of risk.
I guess you don't open many devices. If you did, you'd have noticed the flux residue found in all sorts of equipment, from consumer electronics to IT to test gear to appliances.
Absolutely not.Yes, I understand; it's more practical to create a mod-board than to re-spin the main one, usually.Do you understand, though?? This isn't a mod board as such. A mod board is commonly understood to mean a daughtercard made to implement a bodge to correct an error on the main PCB, rather than making a new main PCB.
As I explained above, early versions of the board had this part of the circuit on the main PCB. Then on this later version, the main board was respun to move that part of the circuit onto a daughtercard.
This isn't a cost-saving measure, as it's more expensive in every way: the added engineering cost, a respun main PCB, a new daughtercard, and the extra labor to solder the daughtercard onto the main PCB.
Even by your own definition, it clearly is a mod board
as the new main board is (what appears to be) not a respin but a new "universal" design, intended to be used in multiple models, but which lacks the onboard capability for these necessary components in a 34465.[/color][/size][/b]
An observation isn’t an ad hominem attack.I know, but that still doesn't make it okAs wraper said, cleaning in situ could get flux residue into places it shouldn't be. And with the two boards soldered together, cleaning becomes much more difficult.
So you'd be adding a cleaning step with no advantage, but plenty of risk.
I guess you don't open many devices. If you did, you'd have noticed the flux residue found in all sorts of equipment, from consumer electronics to IT to test gear to appliances.
Please leave ad hominem attacks where they belong; on the editing room floor (inside your head).
Difficult is not impossible, and the risk is a balance between existing potential for harm, post-cleaning potential for harm, and the additional costs of either having unwanted warranty claims (something we can only speculate about as Keysight will certainly not release such commercially sensitive information), or additional costs of cleaning plus potential unwanted warranty cost as a result of more harm being done than good.
Yes, I understand very well, thankyou, nevertheless it's cosmetically unattractive, and in an instrument where I expect seriously anal levels of cleanliness, it does not sit well.
Absolutely not.
A mod board is a patch made applied after the fact to an existing part to correct an error discovered after manufacturing, so that you don’t have to trash the existing part. They DID redo the existing part, and this board was designed to be there from the beginning of this redesign.
Since we don’t know for sure why those parts were moved off the main board, we certainly can’t conclude that it’s because of making it a universal design. (I frankly doubt that it has to do with reusing the board in multiple models: it’d almost certainly be cheaper to make different boards than to have the added labor to solder on a daughterboard. Remember that that’s just one person’s random guess, not even the result of circuit analysis.)
Also, by what logic is a new board design not a board re-spin? :-DD
An observation isn’t an ad hominem attack.
I said that I guess you don’t open many devices, and that still remains a reasonable assumption, since your surprise at a bit of flux residue in a place where it clearly does no harm (because if it did do harm there, they’d remove it!) would have been tempered by seeing it in device after device. (Either that, or you have opened lots of devices but just haven’t been observant.)
A mod board is a board bodged onto the ORIGINAL board, not to the new version! That’s the difference. If they’re designed to go together — as the new version and its daughterboard are — then it’s not a mod board!!Absolutely not.
A mod board is a patch made applied after the fact to an existing part to correct an error discovered after manufacturing, so that you don’t have to trash the existing part. They DID redo the existing part, and this board was designed to be there from the beginning of this redesign.
You don't think it's an error to design a board that needs to be changed to move some parts to a daughter-board? There is a design error here, whether in the original that required a revision, or in the revision that could not be made to work without the extra expense.
We don’t have any evidence for or against this claim. It could be right, but it could be wrong. So you shouldn’t treat it as gospel at this stage.Since we don’t know for sure why those parts were moved off the main board, we certainly can’t conclude that it’s because of making it a universal design. (I frankly doubt that it has to do with reusing the board in multiple models: it’d almost certainly be cheaper to make different boards than to have the added labor to solder on a daughterboard. Remember that that’s just one person’s random guess, not even the result of circuit analysis.)
Also, by what logic is a new board design not a board re-spin? :-DD
Because it is not a new board intended only for the 34465, it is intended (by fairly obvious implication) to be used at least in the entire 3446X family, and as some have speculated in the 34470 as well.
You also make an unwarranted assumption; that if the flux residue could be harmful, they would remove it. I explained in my last post why this is not necessarily so, and I can assure you I have the relevant experience to make the guesses that I did as to why they did not clean up afterwards.[/color][/size][/b]Your explanation was so difficult to parse that it’s hard to understand exactly what you were saying.
I think you are both right/wrong. As Kleinstein already noted: Keysight did change the board layout but for some reason choose not to redo the entire layout but use an extra board instead. Likely Keysight didn't want to re-qualify / re-test a new board layout given the high performance they want to get out of the design.A mod board is a board bodged onto the ORIGINAL board, not to the new version! That’s the difference. If they’re designed to go together — as the new version and its daughterboard are — then it’s not a mod board!!Absolutely not.
A mod board is a patch made applied after the fact to an existing part to correct an error discovered after manufacturing, so that you don’t have to trash the existing part. They DID redo the existing part, and this board was designed to be there from the beginning of this redesign.
You don't think it's an error to design a board that needs to be changed to move some parts to a daughter-board? There is a design error here, whether in the original that required a revision, or in the revision that could not be made to work without the extra expense.
Again, to spell this out for you since you’re either not getting it, or are being deliberately obtuse: a mod is something designed AFTER a given version is manufactured, to be bodged onto already-manufactured boards. A mod board is, by definition, one for which the board it’s being attached to was not designed to accept.
A reason for the new board could have been the problem they had with the high voltage rating, though the rumors were that this was from the relay ratings.
Likely not related to OP's fault, but something to point out (and I do hope I'm wrong here):I'm afraid you are not wrong. It is a good find though so I appreciate you taking the trouble for digging this up. There is nothing to be found on TI's website about these microcontrollers nowadays. As if they never existed!
TI/Stellaris LM3S1D21 ARM processor is discontinued 2016 and withdrawn from the market due to the flash corruption issues. The parts are a lemon, known about in 2014.
"Flash corruption or device failure may occur at power on"
"Flash memory endurance cycle specification is 100 cycles"
"Flash memory corruption may occur when device is unpowered and stored for several months - Due to the storage oxide thickness and trap-assisted electron tunneling, there are more leaked cell values than originally expected in the Flash design within several months after programming. As a result, the ECC logic is not able to repair all of the errors in the Flash memory. Data derived from customer returns predicts that devices that are left unpowered at room temperature storage for 6 months can result in failure rates of 2000-3000 DPPM per year."
Ref: TEMPEST/INFERNO LM3S Errata Document (Literature Number: SPMZ861 (https://www.ti.com/lit/er/spmz861/spmz861.pdf))
Bench multimeter product line 34461A, 34465A, 34470A use this MCU not as the main front panel processor but I think it's the Inguard processor.
If this is a real problem, silicon revisions need to be confirmed it's all 130nm parts, Keysight should be offering free extended warranty. It would be a massive debacle.
My 34461A also has the LM3S1D21 microcontroller revision A2 which is affected by the flash corruption problem. A way around it, is to leave the device on for at least 24 hours to give the internal flash controller the chance to fix the bits that have gotten corrupted. However, that system isn't failsafe as well and can actually corrupt data which was good. On top of that it is hard to tell whether a corrupted flash is signalled at all and how this affects measurements. It could be that the software continuous on with bad data affecting the measurement results.
All in all these units have a ticking time bomb inside them. :palm:
July 1, 2014 Re: Acknowledgement and Limited Warranty Letter for Stellaris Tempest and Firestorm LM3S MCU Devices
Dear Ladies and Gentlemen:
Texas Instruments Incorporated (“TI”) has identified potential flash memory corruption risks with respect to the Stellaris Tempest and Firestorm LM3S part numbers listed in PCN 20140630000. You are receiving this Acknowledgement and Limited Warranty Letter (“Letter”) because TI records indicate you have purchased or sampled one or more of the LM3S Products affected. TI has made a decision to End of Life (EOL) these LM3S Products that were acquired from Luminary Micro. The Erratum (SPMZ861) for these LM3S Products is available at [url=http://www.ti.com]www.ti.com[/url].
TI did not undertake this EOL decision lightly. TI has undertaken significant diagnostic efforts and has replicated quality and performance issues, including flash corruption, that our customers have reported. TI has not been able to find any system level or manufacturing workarounds that completely prevent the flash corruption issues. Customer reported worst case fail rates for these LM3S Products, while using the entire flash in the largest 512kB configuration, is 0.3%. These issues may continue to manifest themselves as failures in customer designs over time, to a greater or lesser degree, depending on a customer’s system design, proportion of flash memory used, and storage times following a customer’s programming of the flash. Please see the Erratum for more details.
Importantly, we want to assure you that these reported flash corruption issues in the LM3S Products (which were designed using Luminary Micro methodologies) are not present in TI’s next generation TM4 products, which have been designed and produced in accordance with TI’s standard design and production procedures and methodologies. For the reasons explained herein, notwithstanding any provision to the contrary in any Purchase Order or any other purchasing or acknowledgement document, for shipments after September 1, 2014, TI’s sole and total warranty is a limited warranty. This limited warranty of credit or replacement is capped at .3% of the revenue for LM3S Products shipped after September 1, 2014.
When possible, TI will replace LM3S Products prior to the end of the EOL period based on then existing lead times. After completion of the deliveries at the end of the EOL period, this warranty will be limited to credit only. Except for this limited warranty, TI makes no warranty, express, implied or statutory, including any implied warranty of merchantability or fitness for a specific purpose, for these LM3S Products.
TI will not support full customer return analysis and any related corrective actions (8D reporting, cycle time metrics, etc.) for these LM3S Products, because of these known issues and uncertainty on how, or to what extent, these issues will impact actual customer systems. However, TI may, in its sole discretion, perform customer return analysis to verify warranty claims based on flash memory failures.
TI requires this Acknowledgement and Limited Warranty Letter for LM3S Products to be signed by you by September 1, 2014 to continue shipments after September 1, 2014.
If you desire further shipments of these LM3S Products, please have an authorized person sign below to indicate your agreement and acceptance of this Letter, and return a signed copy of this Letter to TI (at the e-mail address below ),or your authorized TI distributor, if you are buying from a distributor. This Letter will become effective upon your signature.
TI will accept cancellations of orders for LM3S Products accepted before July 1, 2014, if those cancellations are made by September 1 2014. Also, TI will accept returns of LM3S Products in customer inventory based on Return Materials Requests received by TI by September 1, 2014, that are undamaged and in original packing.
These LM3S Products should not be used for any safety-critical application in which a failure of the device could result in an injury to persons or property.
FOR CLARITY, PLEASE NOTE THAT ANY ORDERS REMAINING IN PLACE AFTER SEPTEMBER 1, 2014, WILL IMMEDIATELY BECOME NON-CANCELABLE AND NON-RETURNABLE. ANY INVENTORY REMAINING IN PLACE AFTER SEPTEMBER 1, 2014, WILL IMMEDIATELY BECOME NON-RETURNABLE, EXCEPT FOR THE LIMITED WARRANTY ABOVE.
Please do not hesitate to contact your TI representative or your distributor if you have questions.
Very truly yours,
Texas Instruments Incorporated
I just picked up a 34465a on the cheap and noticed that mine has a LM3S1D21 as well. How can I tell the revision of my LM3S1D21?Chip revision does not matter. It's garbage by design, not some bug which could be fixed. Read pages 24-25 https://www.ti.com/lit/er/spmz861/spmz861.pdf?ts=1651046449928&ref_url=https%253A%252F%252Fwww.google.com%252F (https://www.ti.com/lit/er/spmz861/spmz861.pdf?ts=1651046449928&ref_url=https%253A%252F%252Fwww.google.com%252F)
From the ti doc, it looks like my chip was produced September of 2015.
My unit has 2.14 firmware on it, but I have a feeling there is no firmware to fix internal MCU chip nand corruption :/
Thanks!
Chip revision does not matter. It's garbage by design, not some bug which could be fixed. Read pages 24-25 https://www.ti.com/lit/er/spmz861/spmz861.pdf?ts=1651046449928&ref_url=https%253A%252F%252Fwww.google.com%252F (https://www.ti.com/lit/er/spmz861/spmz861.pdf?ts=1651046449928&ref_url=https%253A%252F%252Fwww.google.com%252F)
Shortly Flash is trash by design and can corrupt data when left unpowered for a few months, but ECC is trash too and can read the data incorrectly and then re-program incorrect data :palm:.
TI desperately needed to leapfrog into ARM core or get left in the dust. But then taking 5 years to fully realize the 3rd party FLASH IP used in the MCU's is total garbage?FWIW TI made ARM based SoC (mainly for phones) for at least a decade at the time of acquisition (2009).
LM3GPIO#05 PB1 has permanent internal pull-up resistance
Device(s) Affected: Stellaris Tempest-class Rev C5 and Firestorm-class Rev A2
Description: Regardless of its configuration (GPIO or alternate digital function), PB1 has a maximum
internal pull-up resistance of 800 Ω that turns on when the voltage on the pin is
approximately 1.2 V. Due to this internal resistance, up to 3 mA of current may be
sourced during the transition from 1.2 V to 3.3 V.
Workaround(s): When this pin is configured as an input, the external circuit must drive with an
impedance less than or equal to 300 Ω to provide enough drive strength to over-drive the
internal pull-up and achieve the necessary VIL voltage level. Ensure that the driver can
sink the temporary current. In addition, do not use PB1 in open-drain mode.
If this pin is configured as an output, be aware that if the output was driven High and a
non-POR reset occurs, the output may be driven High after reset unless it has a 300-Ω
resistor on it. Once the pin is configured as an output, the pin drives the programmed
level.
Sorry for asking again, all 34465A DMM's make a relay click sound when central (red) wire is touched? It is a normal behaviour?Does it click if you disable autoranging? Also is it in 10Mohm impedance mode?
Thank you!
In the meantime I had a rather in depth email exchange with Keysight support (without needing to pay or jump through hoops). It looks like Keysight has found the issue with the LM3S1D21 by themselves and reported back to TI. According to Keysight they did some kind of check on the part to see if it is affected before assembly so units in the field shouldn't be affected. In case there is a problem, it shouldn't result in bad/wrong readings. The latter is my main concern.Likely not related to OP's fault, but something to point out (and I do hope I'm wrong here):I'm afraid you are not wrong. It is a good find though so I appreciate you taking the trouble for digging this up. There is nothing to be found on TI's website about these microcontrollers nowadays. As if they never existed!
TI/Stellaris LM3S1D21 ARM processor is discontinued 2016 and withdrawn from the market due to the flash corruption issues. The parts are a lemon, known about in 2014.
"Flash corruption or device failure may occur at power on"
"Flash memory endurance cycle specification is 100 cycles"
"Flash memory corruption may occur when device is unpowered and stored for several months - Due to the storage oxide thickness and trap-assisted electron tunneling, there are more leaked cell values than originally expected in the Flash design within several months after programming. As a result, the ECC logic is not able to repair all of the errors in the Flash memory. Data derived from customer returns predicts that devices that are left unpowered at room temperature storage for 6 months can result in failure rates of 2000-3000 DPPM per year."
Ref: TEMPEST/INFERNO LM3S Errata Document (Literature Number: SPMZ861 (https://www.ti.com/lit/er/spmz861/spmz861.pdf))
Bench multimeter product line 34461A, 34465A, 34470A use this MCU not as the main front panel processor but I think it's the Inguard processor.
If this is a real problem, silicon revisions need to be confirmed it's all 130nm parts, Keysight should be offering free extended warranty. It would be a massive debacle.
My 34461A also has the LM3S1D21 microcontroller revision A2 which is affected by the flash corruption problem. A way around it, is to leave the device on for at least 24 hours to give the internal flash controller the chance to fix the bits that have gotten corrupted. However, that system isn't failsafe as well and can actually corrupt data which was good. On top of that it is hard to tell whether a corrupted flash is signalled at all and how this affects measurements. It could be that the software continuous on with bad data affecting the measurement results.
All in all these units have a ticking time bomb inside them. :palm:
In the meantime I had a rather in depth email exchange with Keysight support (without needing to pay or jump through hoops). It looks like Keysight has found the issue with the LM3S1D21 by themselves and reported back to TI. According to Keysight they did some kind of check on the part to see if it is affected before assembly so units in the field shouldn't be affected. In case there is a problem, it shouldn't result in bad/wrong readings. The latter is my main concern.It's not like that. If you read the errata, you'd know that sitting off for years does not necessarily cause the NAND corruption. It just increases its chance. Staying always ON does not help with corruption either since of garbage ECC circuit which may cause corruption of good data by itself. The flash corruption rates given in ERRATA because of both issues are similar. It's not like there are good chips and bad chips, there is a crappy design.
If my unit where affected, it would have shown by now as it is sitting switched off for periods lasting over a year.
It's now 2024 has this problem been resolved with current production KS3446A DMMs?From my email exchange with Keysight, it looks like they are using a different microcontroller as the microcontroller they used initially has been discontinued.
You can order a new front panel PCA for your 34461A from Keysight here: https://www.keysight.com/us/en/ecom/parts/part-detail.html/34460-66522 (https://www.keysight.com/us/en/ecom/parts/part-detail.html/34460-66522)
Will you ship to non-US countries?
Currently bill-to and ship-to addresses for Parts Online Store orders must be within the United States only.
I was pointing out that online store is US only.Most re-shippers also offer shopping services (shop & forward) so the billing address will be in the US.
Your registered company address and shipping address need to be US, so re-shipper won't work.
...and now Keysight have decided we aren't capable of fitting a new front panel PCB ourselves. They won't sell you one, "contact us for repair", probably at the price of a new unit.
https://www.keysight.com/gb/en/ecom/parts/part-detail.html/34460-66522 (https://www.keysight.com/gb/en/ecom/parts/part-detail.html/34460-66522)