What TL074's are still JFET? - Page 1
Forum section: electronics / beginners

author: K3mHtH
author_rank: Regular Contributor
timestamp: August 07, 2025, 08:41:29 am
content: Now that TI has changed their TL074 fab, the new chips are no longer J-FETs. I'm happy for the power-efficiency but datasheet shows some differences - like audio quality and phase reversal behavior, which some designs might require.TI says TL074A, TL074B, TL074C may now be changed, and new part # TL074H is guaranteed to be the new part. TL074M, the mil-spec version is guaranteed to be the old ones for now.Is this happening with other manufacturers?I know things always change in electronics, but is replacing a part # common?What can be put on a BOM to guarantee a J-FET TL074 equivalent?

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2025, 09:00:16 am
content: I thought the old parts i.e. TL074A, TL074B and TL074C aren't gong to change. The TL074M certainly won't change because it will piss off defense contractors which will be forced to recertify them.I wish companies wouldn't introduce new parts, using a completely different process, with the same part numbers. Give them a new part number and make the old ones obsolete, with a clear note on their website and data sheets about equivalent new parts.Perhaps you could use the STMicroelectronics version?

author: Terry Bites
author_rank: Super Contributor
timestamp: August 07, 2025, 01:19:08 pm
content: TL074H is a jfet amp. Why do you think otherwise?Read the TI datasheethttps://www.ti.com/lit/gpn/tl074h

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2025, 01:37:43 pm
content: Quote from: Terry Bites on August 07, 2025, 01:19:08 pmRefer to the schematic on page 29, which clearly shows MOSFETs. The TL07xH has a CMOS input stage, not J-FET.

author: wraper
author_rank: Unknown
timestamp: August 07, 2025, 01:50:45 pm
content: Quote from: Terry Bites on August 07, 2025, 01:19:08 pmIf you compare 2017 with later datasheets they changed the title fromQuotetoQuote

author: ejeffrey
author_rank: Super Contributor
timestamp: August 07, 2025, 03:52:16 pm
content: Quote from: Terry Bites on August 07, 2025, 01:19:08 pmTake a look at the noise spec. The H has 37 nV/rtHz while the M has 18 nV/rtHz. The A, B, and C have different specs depending on package. It's clearly moved to a CMOS process.

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 04:28:38 pm
content: The July 2025 TI datasheet for the TL07xH devices cited above, with "FET" instead of "JFET" in the title, is the latest version.Nowhere in the entire datasheet is "CMOS" mentioned in prose. The general description reads:"The TL071H, TL072H, and TL074H (TL07xH) familyof devices are next-generation versions of theindustry-standard TL071, TL072, and TL074 (TL07x)devices."The CMOS guts can be inferred from the technical specifications (power, noise, etc.) listed by others above.The simplified schematic on page 27 clearly shows CMOS construction, but the accompanying text does not mention it.

author: E-Design
author_rank: Regular Contributor
timestamp: August 07, 2025, 05:27:26 pm
content: FWIW, I confirmed with a TI rep these did move to a new smaller die, on a CMOS process. Older non "H" parts are also being ECN' to the new die.

author: floobydust
author_rank: Super Contributor
timestamp: August 07, 2025, 05:43:43 pm
content: TI are fuckers in sneakily changing legacy parts over to a cheaper process. JFETs have always been a big hassle in production."As long as it meets the spec" is their mantra. Doubling the noise though?CSO: SFAB (legacy flow) changed to CSO: RFB.Edit: a bit more about CSO. It seems the TI older 150mm wafer fabs are getting upgrades to 300mm and many IC's got affected but we did not notice.CSO (Chip Source Origin) - Fab Wafer factory location (city)CCO (Chip country of origin) - Country where fabrication occursASO (Assembly source origin) - Assembly site originACO (Assembly country of origin) - Assembly country originRFB (2021), RFAB (RFAB2, RFAB1) are the Richardson, Texas giant 300-mm analog wafer fab. R for "Richardson" I think."These changes are part of our multiyear plan to transition products from our 150-millimeter factories to newer, more efficient manufacturing processes and technologies, underscoring our commitment to product longevity and supply continuity."S or SHE for "Sherman" Texas I think. 150mm closing and getting 2-4 new fabs there, under construction.LFAB (Lehi, UT) – Acquired from Micron, started in 2023CFAB CU3 CHN Chengdu

author: tooki
author_rank: Super Contributor
timestamp: August 07, 2025, 05:52:13 pm
content: Quote from: floobydust on August 07, 2025, 05:43:43 pmCan you elaborate on that statement? I know next to nothing about semiconductor processes, but am just curious.

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 05:57:40 pm
content: The latest datasheet I found for the LF411 (formerly NSC, now TI), dated October 1997, explicitly states "JFET".Has that status changed?

author: K3mHtH
author_rank: Regular Contributor
timestamp: August 07, 2025, 05:59:39 pm
content: Quote from: Zero999 on August 07, 2025, 09:00:16 amDo we know the STM version is J-FET?

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2025, 06:06:17 pm
content: Quote from: K3mHtH on August 07, 2025, 05:59:39 pmYes. Assuming they've not lied on their data sheet.www.st.com/resource/en/datasheet/tl074.pdf

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 06:12:35 pm
content: That STM datasheet is dated November, 2013.

author: tooki
author_rank: Super Contributor
timestamp: August 07, 2025, 06:20:39 pm
content: Quote from: TimFox on August 07, 2025, 06:12:35 pmAnd? If they haven't changed the product for years, there would be no changes needed to the datasheet.

author: wraper
author_rank: Unknown
timestamp: August 07, 2025, 06:21:12 pm
content: Quote from: TimFox on August 07, 2025, 06:12:35 pmSo what? There is no newer version.

author: magic
author_rank: Super Contributor
timestamp: August 07, 2025, 06:25:59 pm
content: Quote from: TimFox on August 07, 2025, 04:28:38 pmI think it's a matter of marketing to the audio industry, which uses plenty of TL07x. Similar secrecy exists around their OPA16xx audio-specified opamps: if it says "FET input", you can be absolutely sure it's CMOS and they sometimes reluctantly admit so in a fine print somewhere, while JFET parts are prominently advertised as such, with claims like "true JFET input" or "superior sound quality of JFETs"Of course there is no way around the fact that TL07xH is a flicker noise monster. Looking at that plot, I'm pretty sure that I could hear it hissing running at unity gain and driving a pair of sensitive headphones. That's just lame, basically LM358-tier performance near 1kHz. People who care will not switch over, and they will be pissed.

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2025, 06:35:48 pm
content: I've done some searching and found the TL07x-EP is available from TI and is listed as a JFET input op-amp.https://www.ti.com/lit/ds/symlink/tl074-ep.pdfhttps://www.ti.com/product/TL074-EPThere are also other suppliers such as the Taiwanese compand Unisonic Technologies. I've no idea whether it's any good or not.https://www.unisonic.com.tw/uploadfiles/836/part_no_pdf/TL072.pdf

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 07:02:52 pm
content: Quote from: wraper on August 07, 2025, 06:21:12 pmJust making a statement of fact.How does one know that no newer version exists?

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 07:04:47 pm
content: Quote from: Zero999 on August 07, 2025, 06:35:48 pmThe two TI datasheets linked are from December 2012.

author: Zero999
author_rank: Super Contributor
timestamp: August 07, 2025, 07:24:56 pm
content: Quote from: TimFox on August 07, 2025, 07:04:47 pmOne of their engineers more recently made a post on their forum which shows a schematic of the TL074-EP with a JFET input stage.https://e2e.ti.com/support/amplifiers-group/amplifiers/f/amplifiers-forum/1381697/tl074-ep-short-circuit-currentPerhaps the TI forum is a better place to ask this question?

author: chilternview
author_rank: Frequent Contributor
timestamp: August 07, 2025, 07:26:32 pm
content: Quote from: tooki on August 07, 2025, 05:52:13 pmMy days of process development were 40 years ago, so things may be very different. But (if I recall correct) back then jfets were sensitive to diffusion - the n channel was sandwiched between p type diffusions. This was harder to control than a mos device whose main variability was the gate oxide thickness. Edit: the end result meant the threshold voltage of jfets was hard to control.But I suspect CMOS has just become better, and modern CMOS can also have bipolars, so the old processes just aren't so good. Except for noise - jfets were inherently less noisy than mos devices.

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 07:30:28 pm
content: Before retirement, I worked with analog front ends for x-ray detector arrays.We used premium op amps for the input stage (transresistance), and then TL074s, etc. for the successive stages (integrator, track-hold) before digitization.The increased noise from the modern CMOS devices would have degraded the overall performance in that application.

author: floobydust
author_rank: Super Contributor
timestamp: August 07, 2025, 07:32:19 pm
content: Quote from: tooki on August 07, 2025, 05:52:13 pmI meant the huge spread in IDSSthat makes the discrete JFET a bitch in production, avoided by EE's. Hand selected is not realistic nowadays. This is all in linear mode, not as switches.I'm not an expert in semiconductor fab to know why, and why it was not really conquered over the decades.For an IC op-amp, trims became the norm. But this is expensive, an extra step.I don't find any die-shots of the 074.TL084the JFET's are huge and I don't see any trims.For TI, this could be two or three cost savings using mosfets.Having trouble believing the (H) input capacitance is 1pF common-mode and 2pF differential. It should double for common-mode? and they've added input clamp diodes on the new die so 1pF seems a bit lean.I assume one could use the ST version? Less hisssssssssssssss.

author: wraper
author_rank: Unknown
timestamp: August 07, 2025, 07:54:58 pm
content: Quote from: TimFox on August 07, 2025, 07:02:52 pmLike checking documentation on ST website?

author: TimFox
author_rank: Super Contributor
timestamp: August 07, 2025, 08:50:06 pm
content: Quote from: wraper on August 07, 2025, 07:54:58 pmNo aspersions cast on the ST website.However, I have seen many drastic changes, including shutting down operations, that are never posted and the obsolete website pages persist.Of course, RCA published its curves on the 6L6 back in 1934 and never revised them until they pulled out of the industry in the 1980s (for the 6L6GC).

author: magic
author_rank: Super Contributor
timestamp: August 07, 2025, 08:54:28 pm
content: Quote from: floobydust on August 07, 2025, 07:32:19 pmNot necessarily. Source follows the gate, so most gate-source capacitance is bootstrapped away. Gate-drain can also be almost eliminated by bootstrapped cascode. Gate-substrate is a big deal in vintage JFET opamps like TL072, not applicable to CMOS or SOI JFETs (or at least much reduced). But differentially it's a different story: you must charge/discharged those gate-source capacitors to make a difference in respective Vgs, no way around it.Other examples with Cdiff > Ccm are OPA1641 or AD797 (BJT) if you don't trust TI. Basically, anything with large, low-noise, undegenerated input transistors and bootstrapped cascode. And not a JFET or PNP on a vintage process, those have big substrate capacitance which adds up in common mode.

author: David Hess
author_rank: Super Contributor
timestamp: August 07, 2025, 09:22:45 pm
content: I wonder how they got a 36 or even 42 volt differential input range with MOSFETs. Linear IC process MOSFETs are usually limited to 16 volts or less.The input bias current looks like JFETs, but the noise and dynamic performance look like MOSFETs.Quote from: tooki on August 07, 2025, 05:52:13 pmJFETs require extra processing steps like ion-implantation.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 07, 2025, 09:52:49 pm
content: With CMOS one can get high voltage rating with a thicker gate oxide and not super short channels. There are quite some power MOSFETs that are rated for 30 V gate voltage, though modern parts are often limited by a protecting zener. It does not need that much more oxide thickness to get a higher voltage rating. A thicker oxide also comes with less leakage, but of cause with less gain too.Higher voltage CMOS is used with analog switches already for quite some time. Here quite some parts are rated for 44 V and few even higher.Ti has quite some 40 V rated CMOS OP-amps, like OPA990. Some also get away without the diode clamping between the input.The TL072H is a bit special that it has a CM range to the positive supply and not the negative supply.The input bias specs may not have been updated from the old JFET version. No need to introduce strickter test limits.

author: floobydust
author_rank: Super Contributor
timestamp: August 08, 2025, 12:00:54 am
content: Quote from: magic on August 07, 2025, 08:54:28 pmWhat package accomplishes this? 2pF differential. I thought that to be very low input capacitance value, lowest in town. I could only find 6-9pF for other CMOS parts. We don't know what it was for the old JFET version and a drop only an issue for stability with photodiode amps etc. I imagine.Am I the only one that knows about these part's (074, 084) phase-inversion? I like how TI whitewashed that off the datasheet and graph says "No Phase Reversal" counter to reality. From the TI forum "... only the TL084H section of the curves states 'no phase reversal'. However the other versions do not make that claim. The classic TL084 will fully phase invert as you have seen.""A correction still needs to be made because TL084H will phase invert to a lesser extent. When the input common mode is too close to the V- supply, the device can invert. In your example circuit, when input becomes too low the input stage will cutoff. In cutoff, the output may go high or low. If output wants to go low, VOL will occur. If output wants to go high the output will start to go high, but just high enough to bring the common mode (at IN-) back into operation (not cutoff)."Why can't TI be honest, the old datasheet showed the inversion and gain non-linearity. Or just renumber the IC, it's different.89 page datasheet that is 40+ pages of packaging information that doesn't belong in a datasheet. It belongs with the packaging information. Why put pages of dimensions there, other than to pad this mess and achieve scorecard greatness lol.

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2025, 07:43:11 am
content: I thought phase inversion of JFET input op-amps was such common knowledge it's assumed, unless the data sheet says otherwise.There's the LF353 and LF347 which are very similar to the TL072 and TL074 and still are JFET input.https://www.ti.com/lit/ds/symlink/lf353.pdfhttps://www.ti.com/lit/ds/symlink/lf347.pdf

author: Kleinstein
author_rank: Super Contributor
timestamp: August 08, 2025, 08:00:55 am
content: The Ti PCN note also lists the LF353 and LF347. So for the Ti part one will have the same uncertainty about which version one would get.I think is was a really bad idea of Ti to do such a drastic change in the parts and still keep the old number.Already the first step with the TL072H was confusing, but now selling 2 very different part under the same number is a big no go. The Ti TL07x parts are now essentillially unusalble for a commercial product. One could as well buy parts from the Chinese gray market. In both cases one would need to test the parts (at least each lot) first. Even if the application is relatively uncritical, a different part can effect things like EMI.2 quite different parts in one datasheet complicated things - there are very few points they really share, excepts the pinout and case drawings.The package dimensions in essentially evenry data-sheet are due to the mess with package names. In the electronic form the extra pages are not hurting that much. It is a point that should ideally be recfied, but that is not Ti specific and a different topic.

author: MrAl
author_rank: Super Contributor
timestamp: August 08, 2025, 08:30:59 am
content: Quote from: K3mHtH on August 07, 2025, 08:41:29 amHi,I've only read about a few cases where they actually used the same part number for a modified part, and modified enough where it would no longer work in the original applications. Over many years though only maybe 3 parts in total. That's over 50 years and only 3 parts. I guess there could be more I don't know about though.From what the others here are saying it does not sound like this part really changed though.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 08, 2025, 08:55:14 am
content: Chances are they would change the parts once the stocks of old JFET parts are depleted. So while the PCN was aready some time ago, they may not have delivered many CMOS verions under the old part number.Delivering a much different part is an odd way to cover up that they no longer want to deliver the old jelly bean part, except in the expesive mil spec version or rare (old ?) wide body SOIC where they may still have plenty of stocks.The old cases where parts changes where usually more gradual changes.

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2025, 10:54:15 am
content: Quote from: Zero999 on August 08, 2025, 07:43:11 amOh dear. It looks like it's not the first time they've done this. There's the LF353-N and LF347-N which are similar to the LF353 and LF347, but with a wider bandwidth and slightly higher noise.I believe they're still JFET, but more noise and especially wider bandwidth could cause problems in some applications.https://www.ti.com/lit/ds/symlink/lf353-n.pdfhttps://www.ti.com/lit/ds/symlink/lf347-n.pdf

author: magic
author_rank: Super Contributor
timestamp: August 08, 2025, 11:11:41 am
content: IIRC they added -N suffix to some National chips in order to avoid name clash with their own versions of the same part.The two datasheets that you linked look like National datasheets, and those linked earlier look like TI.

author: Terry Bites
author_rank: Super Contributor
timestamp: August 08, 2025, 11:25:40 am
content: When and where does the TI information come from? "TI says TL074A, TL074B, TL074C may now be changed, and new part # TL074H is guaranteed to be the new part""Now that TI has changed their TL074 fab, the new chips are no longer J-FETs"Changed to what and when? This is BS!Are you confusing the TL07x with the MOSFET TLC07x? The TLC07x have lower In and Vn than the Jfet part.The TLC07x is not a drop in replacement for the TL07x Jfet part so why would they discontinue it?www.ti.com/lit/gpn/TLC074Awww.ti.com/lit/gpn/tl074Are you reading the ST data sheet for their Jfet 074.The data sheet has a schematic of the opamp clearly showing Jfets.ST do not make the CMOS version. TI is the sole Mfr of the MOSFET TLC07xBeing that it is a very common jellybean part it's incredibly unlikely that they'll make it obsolete in the near future.Its a good earner for all second sources too.

author: David Hess
author_rank: Super Contributor
timestamp: August 08, 2025, 11:32:41 am
content: There are a lot of old parts which use the same junction isolated NPN plus JFET process, and as far as I know, it is old news that they are being moved to a newer process. I found a change notice from Digi-key which is 2 years old, attached below.I do not see anything about the TL074H replacing the older parts.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 08, 2025, 11:59:09 am
content: The information is in the new TL07x datasheet (updated july 2025).In addition to the information in the table there is some more in the text, that the NS and PS case (wide SOIC) are still the old JFET die.Ideally there should also be PCN on this - if not this would be another fail.

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2025, 12:09:03 pm
content: It would be acceptable, if they just appended the N and created a new data sheet for the new part. Then, there wouldn't be any confusion. If the no longer make the classic TL07x, then they should make it obsolete and clearly point to the H-versions as replacements.

author: ejeffrey
author_rank: Super Contributor
timestamp: August 08, 2025, 02:16:23 pm
content: Quote from: Terry Bites on August 08, 2025, 11:25:40 amRead the messages above?TL072 now has a CMOS part which is replacing the jfet part in most cases under the same part number. It's in the TI data sheet. The CMOS TL072 is different than the TLC072 in that it maintains the full operating voltage range of the jfet version.

author: TimFox
author_rank: Super Contributor
timestamp: August 08, 2025, 02:23:49 pm
content: Just commenting on nomenclature:“TLC072” is obviously different from TL072, just as 74C04 is different from 74LS04.It is misleading to change the suffix to indicate a major change in the physical part.

author: MrAl
author_rank: Super Contributor
timestamp: August 08, 2025, 03:21:25 pm
content: Hi,Maybe we should set the record straight here...First, it's not 'really' the same part number. The TL074 was given the suffix as everyone knows now. It is the TL074H as everyone knows.That's not really the same part number, and what's more is that this is a common thing to do. In the past, we've see countless "A" versions come out. That is for example an op amp with an "A" suffix like LM358A. This is a very common thing and as far as I know has been around since maybe the 1970's maybe even before that.What that 'A' means is better specs. It might have faster slew rate, wider bandwidth, etc. And that is exactly what we are seeing with the "H" version of the TL part we are talking about.So in the end, adding an "H" is nothing really new, it's been done a lot before. It's a performance enhancement.If you need the old TL074 with no suffix or a different suffix, then buy that one and totally ignore the "H" version. If they stop making the older version that would be nothing new either. We have to adapt. I don't like it either but that's progress.As far as I know now, the improvements include the following:Higher slew rateWider supply voltage rangeBetter temperature rangeLower input offset voltageEnhanced noise and RF interference rejectionYet it's pin for pin compatible with the older version.(Anything you don't like in this list? Then don't buy it)This does not surprise me one bit really. The recommendation is to use it in NEW designs. That means we have a new part to work with now. If we need the old part, then we have to try to purchase that. I realize that may get hard to do if they stop making the older version, but most of us here have learned to live with that already. An example is the old sine wave generator/shaper chips that went totally out probably due to low interest in the market. I did not like that either but that's the way things change in the industry.Just to note, I was happy to find a better version of the LM358 when I did find it. In fact, I had to go with an even better chip that was pin compatible for one project. It was the same pinout but higher bandwidth, faster slew rate. That's exactly what they did with this part so I would have welcomed it if that was the older part I was using. In fact, with the higher slew rate that means the power bandwidth would improve too. That can be very desirable in new designs.Note in the above I may have used the word "progress" incorrectly (ha ha).

author: magic
author_rank: Super Contributor
timestamp: August 08, 2025, 03:29:04 pm
content: Quote from: MrAl on August 08, 2025, 03:21:25 pmI humbly suggest reading the thread you are responding to before writing an out of topic wall of text to "set the record straight"

author: wraper
author_rank: Unknown
timestamp: August 08, 2025, 03:40:53 pm
content: Quote from: MrAl on August 08, 2025, 03:21:25 pmAnd you muddied the waters without reading the topic. TL074H is one thatis guaranteedto have the new die, the rest (except TL074M)is a crapshootof what you get, which is more like bait and switch because part number was not changed whatsoever. Most likely all will be CMOS once existing stock of old chips is depleted.

author: floobydust
author_rank: Super Contributor
timestamp: August 08, 2025, 04:13:38 pm
content: TI needs to append a "BULL" suffix for bullshit ethics. Best thing about cow dung is no amount of icing or perfume will cover it up.Sneakily changing from "JFET" to "FET" but not "MOSFET".Gross "improvements" in performance mean it's not fully compatible in circuits using the classic JFET part - so why are they allowed to keep the root part number? This move reminds me of Boeing- they can't make anything new, just rehash the old, keeping the 737 number forever.It has over double the voltage noise, I like the hisssssssssssss which is a major fail in a part well known for use in audio applications. Not an improvement.The "H" is now sole-sourced? Expecting us to design in a multi-sourced part that is now exclusive to TI?The "merged" datasheets is another dog's breakfast, jumbled information marketing was in there to "make it look way better" cherry pick the graphs as well.I laugh because Richardson TX fab is building... cheapened jellybeans? All those billions $ and they can't beat 1978 tech even with 300mm wafers? This is so lame.

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2025, 04:31:24 pm
content: Quote from: TimFox on August 08, 2025, 02:23:49 pmI don't have a problem with that, but the way they're put on the same data sheet creates confusion,The 74LSxx and 74Cxx are clearly made using different processes and have different data sheets.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 08, 2025, 04:36:42 pm
content: The situation with the TL072H was not ideal, but still OK.The problem with the PCN and info in the new datasheet (rev. W from july 2025), it is no longer clear which version you get. It can still be the old die or it can now also be the new die and actually a TL072H. Its only be the details on the lable on the reel that will tell the fab and from this one could infer if it is a JFET or CMOS part.Not knowing what parts wold be sold under a given number is a big no go.Let's hope the distributors would check the lables careful an let people know before ordering.Ideally TI would correct things as fast as possible and return to clear labeling. So the old JFET parts may no longer be available from TI and the users would have to order the new H version if it is OK for them.Currently the normel TL07x from Ti should be a no go - on par with gray market parts from China.If you want the CMOS version buy the H version, if you want the JFET version buy an ST part (with anyway slightly better noise specs).

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2025, 04:49:45 pm
content: TI have also done this with the LM317L. The legacy chip has a minimum load requirement of 2.5mA, and the new chip has a minimum load requirement of 5mA. What's bad is they've not changed the part number, so it's impossible to know what chip you have. Too bad if you've designed your circuit for the lower output current, then it stops working properly with the newer parts.https://www.ti.com/lit/ds/symlink/lm317l.pdf

author: tooki
author_rank: Super Contributor
timestamp: August 08, 2025, 04:53:35 pm
content: Quote from: MrAl on August 08, 2025, 03:21:25 pmThat’s a very long-winded way to say “I don’t actually know what I’m talking about in this case, and I didn’t bother to even skim the thread, but nonetheless I’m confidently incorrect enough to try and pontificate to everyone else”.If it had happened the way you describe, nobody would be complaining. But it didn’t, and in this case I think TI’s behavior is deserving of the severest of condemnation.

author: wraper
author_rank: Unknown
timestamp: August 08, 2025, 05:05:06 pm
content: Quote from: Zero999 on August 08, 2025, 04:49:45 pmLM317MLM317LLMAO, did they swap the dies between those?

author: MariuszD
author_rank: Regular Contributor
timestamp: August 08, 2025, 08:29:16 pm
content: People who buy components are not always engineers. For a colleague who deals with purchasing and assembly, finding the differences between TL074B and TL074H will be very difficult.

author: TimFox
author_rank: Super Contributor
timestamp: August 08, 2025, 08:50:39 pm
content: Quote from: MariuszD on August 08, 2025, 08:29:16 pmWhen it is important, the engineer must be very careful in listing components in the BOM to avoid misunderstandings by the purchasing department.I once specified a tantalum capacitor (that had lower than normal ESR) by manufacturer's part number but purchasing substituted a capacitor with the same capacitance and voltage rating from another manufacturer since it was cheaper.

author: Terry Bites
author_rank: Super Contributor
timestamp: August 09, 2025, 08:13:26 am
content: Yeah.Whats going on with this guy?

author: voltsandjolts
author_rank: Unknown
timestamp: August 09, 2025, 09:40:42 am
content: Quote from: MariuszD on August 08, 2025, 08:29:16 pmA useful term for some BoM line items is "DO NOT SUBSTITUTE"

author: MrAl
author_rank: Super Contributor
timestamp: August 09, 2025, 01:43:36 pm
content: Quote from: wraper on August 08, 2025, 03:40:53 pm"Muddied"? That's an interesting word. Luckily, in these forums if you post something incorrect and somebody calls you on it you can always redact it. It's easy to edit here although some forums are not like that they may only give you 30 minutes to correct typos.I guess you were referring to this line:"TI says TL074A, TL074B, TL074C may now be changed, and new part # TL074H is guaranteed to be the new part. TL074M, the mil-spec version is guaranteed to be the old ones for now."But you have to realize that I have trouble believing they would do that. That would cause problems with older devices that need a direct replacement.But more to the point, the first five words do not tell us what is really happening either. Are they swapping the A, B, and C versions, or can they mix in the H version too with those.Also, what is the reason for this and what other information do they provide with this. Knowing the reason could make all the difference. If I had to guess, they are trying to reduce their workload with older parts and this could be due to low sales. But then I do have to also call out the choice of words again. "may" as in "may now be changed", which is like saying nothing at all. They "may" be changed, but then maybe they won't be changed. It "may" rain outside later, but that also means maybe it won't, so do I bring an umbrella with me or not.In other words, an alternate statement for "they may change them", is "maybe they won't change them".The bottom line is I just did not believe part of what I was reading. I think we need to know exactly what has been "changed". Did they merge all three versions, or ship randomly any version, or did they cut off three of the pins of each packageFor proof we need a link to the TI site itself that explains this, and if it is not clear or even seems unreasonable, we have to contact TI directly.Since you took the time to post this information, I'll look for some valid links, and I'll update my previous post about the H version. If I find any valid links I'll update even more. If there are any links in this thread I'll see what they have to say, but only if they lead directly to the TI site and it has specific and definitive information on this.Thanks to the members that looked into this.It looks like there could be a move to simplify documentation without actually changing the parts themselves. That is, internally they may be keeping the parts as they were in the older data sheets. Unfortunately, this means we would have to trust TI's ability to work with the individual parts internally. This really is unfortunate.Did anyone contact TI yet? That's what it is going to take, and then there will still be the trust issue.This seems to be following my proverb for the future: "Everything just keeps getting stupider".If the data sheet no longer reflects the individual specs, that's definitely stupider. Jumbling things together when they are different is always an act of stupidity.This happens with software also. A possible explanation is that when new people get hired they think they see good shortcuts when really they mess up the software, and they never try to use it for real life applications themselves.

author: tooki
author_rank: Super Contributor
timestamp: August 09, 2025, 02:05:41 pm
content: Quote from: MrAl on August 09, 2025, 01:43:36 pmYoureallyneed to learn to read the whole threadbeforewriting. Because then you’d know that this was already done.

author: MrAl
author_rank: Super Contributor
timestamp: August 09, 2025, 02:14:12 pm
content: Quote from: tooki on August 09, 2025, 02:05:41 pmHi,Ok then I apologize, but I often don't have the time to read the entire thing.So apparently you are going to make me look through the whole thread to find it? A link would have been nice

author: wraper
author_rank: Unknown
timestamp: August 09, 2025, 02:19:19 pm
content: Quote from: MrAl on August 09, 2025, 02:14:12 pmIt's literally written in the original post this thread starts with.Quote from: K3mHtH on August 07, 2025, 08:41:29 am

author: MrAl
author_rank: Super Contributor
timestamp: August 09, 2025, 02:21:11 pm
content: Quote from: tooki on August 08, 2025, 04:53:35 pmI have to agree in part, I just didn't have time this time around.What is creeping in here is starting to sound like Class Action Lawsuit.

author: MrAl
author_rank: Super Contributor
timestamp: August 09, 2025, 02:26:00 pm
content: Quote from: wraper on August 09, 2025, 02:19:19 pmWell the main issue seems to be ambiguity in the new 2025 data sheet.Now that I think back, I have always disliked some of the TI data sheets because they tend to reduce the amount of information that we had seen in the old National data sheets. So they have always been a sort of slip shod organization.The bottom line here is does anyone need the older chips anymore. Is it possible to order a similar part from maybe LT. Skip TI altogether.

author: David Hess
author_rank: Super Contributor
timestamp: August 09, 2025, 05:28:14 pm
content: Quote from: MrAl on August 09, 2025, 02:26:00 pmTexas Instruments has always been bad about their datasheets as far as I know, and other manufacturers often competed with them on this basis. Now that they have bought their competition, what little pressure was on them to improve their datasheets is gone.QuoteThe virtue of the TL071 series is their low cost. When I checked a couple years ago, inexpensive modern replacements like the TLE2071 were more than 3 times the cost, and not much better.

author: magic
author_rank: Super Contributor
timestamp: August 09, 2025, 05:29:43 pm
content: Economies of scale. Their bean counters have learned their lessons and the latest "improved substitute" no longer has a different name.I wish I could confidently say that I'm only kidding

author: David Hess
author_rank: Super Contributor
timestamp: August 09, 2025, 10:02:25 pm
content: Quote from: magic on August 09, 2025, 05:29:43 pmIt has an H immediately after the part number, in place of the I, A, B, or C. Hopefully TL074 buyers are used to including the first letter by now. The 741 included parts without a letter.I see that the H versions are also now the least expensive versions, although not available in DIP packaging.Considering the differences with the H version, I think at worst Texas Instruments is taking advantage of the confusion of a similar part number, like the 2N3055H or TIP3055, and no doubt others. At least they used an "H" instead of a "D".

author: magic
author_rank: Super Contributor
timestamp: August 10, 2025, 06:59:28 am
content: Not so fast, the H version is marked D on the packageAnd this thread is about TI's latest datasheet officially stating that they are transitioning old part numbers (TL072C etc) to the H die; only M versions remain guaranteed to be JFET and the rest is lottery.Not sure what happens to their other BiFET products like LFxxx, or LFxxx-N (National's versions) or Burr-Brown OPA604, OPA2134, etc.

author: MrAl
author_rank: Super Contributor
timestamp: August 10, 2025, 07:03:35 am
content: Quote from: David Hess on August 09, 2025, 05:28:14 pmHello,Well I sort of let cost be a secondary issue when it comes to getting a circuit that actually works.We see now that TI is going to be hit or miss, and that's not something that we can tolerate in a design, so I don't see any other reasonable option just yet.Maybe one option would be to buy three times the number of parts needed and then test them for functionality. That can't be cheap either though.

author: David Hess
author_rank: Super Contributor
timestamp: August 10, 2025, 07:38:19 am
content: Quote from: magic on August 10, 2025, 06:59:28 amThe original post did not link anything saying that, and I did not find any links to datasheets saying it. What is the link and which page?

author: magic
author_rank: Super Contributor
timestamp: August 10, 2025, 08:26:57 am
content: July 2025 TL07xx datasheet, section 9.1, page 34.

author: wraper
author_rank: Unknown
timestamp: August 10, 2025, 08:37:14 am
content: https://www.lcsc.com/search?q=tl074h&s_z=n_tl074hLooking on pictures from LCSC, SO package has H marked, TSSOP does not.

author: magic
author_rank: Super Contributor
timestamp: August 10, 2025, 10:03:33 am
content: 1- or 2- channel version in SO8 is marked TL07xD, according to the "packaging information" table in the DS.I guess it's that last D from "HID" on SO14 package, H is omitted.

author: wraper
author_rank: Unknown
timestamp: August 10, 2025, 12:14:17 pm
content: Quote from: magic on August 10, 2025, 10:03:33 amThere is H on SO-14 as shown in my post above.

author: David Hess
author_rank: Super Contributor
timestamp: August 10, 2025, 04:27:59 pm
content: Quote from: magic on August 10, 2025, 06:59:28 amComparing the July 2025 TL07xx datasheet to my 2005 datasheet does seem to indicate that. The H version's specifications fit within the specification limits of the old datasheet, but Texas Instruments is going to have a lot of unhappy customers if they do this. It seems pretty bold, even for them.

author: Terry Bites
author_rank: Super Contributor
timestamp: August 12, 2025, 08:18:13 am
content: I must be hard of reading.