LM317HV and TL783 regulators--no stock

[FredForssell]

I have no immediate need for the regulators. I've used them a few times in the past for various projects, and also needed them for repairs to equipment. I was concerned about the apparent lack of inventory for any future needs.

Bri

Brian,

How many of the TL783 TO-220 do you need?

I have a bunch of them and don't use the through-hole version any more.

Fred

 

[mhelin]

You can use a regular 317 if you put there a pre-regulator before 317 to keep the input - output voltage below some safe voltage level. That can be like a capacitance multiplier with a zener (like 18V) connected from the base of the pre-regulator transistor to the output of 317 like is done on this video:

Now, if you could design a small PCB (SMD) using that kind of design you could build something like a 7848 regulator (for 48V supplies, or even more for some regulated B+ supplies) with the 317 pinout and just short the ADJ pin on your G9 or whatever PCB to ground.

 

[Brian Roth]

It's very easy to purchase from TI. They even will make custom length reels.

Well, tried to log in to the TI website to buy products. Endless "click on any pix with a fire hydrant" or "click on any pix with a bus". Endless worthless waste of time after 10+ minutes. Guess I cannot ever buy TI parts since Mouser and Digikey have no stock until 2023 or 2024.

Screw TI!

Bri

 

[MidnightArrakis]

Well, tried to log in to the TI website to buy products. Endless "click on any pix with a fire hydrant" or "click on any pix with a bus". Endless worthless waste of time after 10+ minutes. Guess I cannot ever buy TI parts since Mouser and Digikey have no stock until 2023 or 2024.

Screw TI!

Bri

I was able to log-on to the TI website with no problems and checked out the two voltage regulators being discussed and it was revealed to me that both of these devices are currently Out-Of-Stock at TI (See images below). So, it probably doesn't much matter.





JBW

/

 

[Brian Roth]

Hey JBW...I seem to have problems with those "click on a pic with a traffic light" anti robot pages....maybe poor eyesight combined with crappy challenge pics. Shrug.

At least I found some 317HV regulators via Jameco, in case I ever need them again! TL783...no dice because I don't buy parts from Ebay or Alibaba...ever...because they are scams.

Curious....any luck with TL072 in a DIP package from the TI website? Before everyone screams at me to use a newer surface mount version...I keep inventory for repairs more than for new design. Yep, I can get Brown Dog adapters....but they are more expensive than the actual chip. Plus, often the adapter won't fit onto a "tight" PCB design with other parts stuffed nearby.

Thanks,

Bri

 

[ccaudle]

any luck with TL072 in a DIP package from the TI website?

Digikey has the TL072BCP variant in stock, TL072B variant, commercial temperature range, DIP package.

Wait, I just noticed that Digikey has started doing that Amazon thing where they have parts listed, but if you look at the details it isn't really from Digikey. Those are listed as "Digikey marketplace" parts that ship from Rochester Electronics.

 

[13engrsapper]

I have no immediate need for the regulators. I've used them a few times in the past for various projects, and also needed them for repairs to equipment. I was concerned about the apparent lack of inventory for any future needs.

Bri

I owe you a favor or two Brian, keep me/us in mind if you are ever in need of small parts like this, or passives, switches, transistors, etc, we have pretty good inventory. I have been worried about lack of availability for a few years and started pack-ratting stuff away - I guess decades ago.

-Tony

 

[Brian Roth]

Hey Tony....I like that term "pack-ratting"! I've been doing the same thing myself for a long time, especially when I was traveling a lot doing on-site work. The sudden disappearing of once common parts set off alarm bells.

I'm semi retired now and don't/won't travel anymore. But, I keep myself from getting bored by doing "selected" projects that arrive here....things like desks, tape machines, outboards and the occasional guitar amp or keyboard. I also maintain a local fleet of eight Ampex ATR-100 machine as well as the electronics portions of a disc lacquer cutting system.

Anyway, I'll send you a PM. Thanks for your assistance!

Bri

 

[chilidawg]

I definitely wouldn't do that, I've heard personally from a board manufacturer horror stories about how in desperation they bought chips from China that couldnt be sourced anywhere else, produced an entire batch of boards and none of them worked brcause the ICs were fake.

On other parts that are most likely to be counterfeited (Burr-Brown, Analog Devices, obsolete audio/power transistors) yes, I agree with you, but for ICs like regulators, almost 99% of them being sold in where I live are sourced from China, made by unknown manufacturers, but they work fine. Occasionally you get some that are DOA, but because they're so cheap, it's forgivable. I have also personally bought parts from eBay (sellers based in China) and they turned out ok too.

 

[gyraf]

..problem is that this is not a generic part, but a specialized one with only one OEM supplier. China does not have an equivalent - so you're 95%sure to get a re-marked 7812..

/Jakob E.

 

[user 41968]

Saw this day coming a long time ago. I have a few TL783 in stock. TL783CKC HV Regulator

 

[Nyquist]

For anyone that didn't know there is a way to use standard LM317 regs for 48v phantom. I've been using this design for around 8 years with no issues.

http://www.jlmaudio.com/JLM PowerStation Ver 2 Schematic.pdf

 

[analogguru]

For anyone that didn't know there is a way to use standard LM317 regs for 48v phantom.......

..... as long as the input to output voltage difference doesn't become more than 40V, e.g. due to a short.
Afterwards the LM317 may be broken.....

 

[rock soderstrom]

..... as long as the input to output voltage difference doesn't become more than 40V, e.g. due to a short.
Afterwards the LM317 may be broken.....

The TL783 does not behave differently with a short. They are always at the front of the line when it comes to dying. TL783= wimpy suckers ☠

 

[analogguru]

The TL783 is at least specified for 125V input/output voltage difference. Of course there can occur a problem with insufficient cooling.

 

[gyraf]

..the problems with TL783 comes only with too large or reversed in/out voltages. In a protected circuit like e.g. in the G9 (charging/discharging timing resistors, zeners), it will only die if output is shorted (creating sudden large in/out differential)..

And no, the 317 can't be used in stead, even if the voltage across it can be limited to safe 40V, the current sourcing needed for stable function prevents it from being really usable above some 50V

 

[rock soderstrom]

The TL783 is at least specified for 125V input/output voltage difference. Of course there can occur a problem with insufficient cooling.

In my experience, this is not just insufficient cooling. These guys are super sensitive, just poke with the measuring tip in the wrong place in the circuit and the TL783 is dead. Just my experience. I try to avoid those by now. I do not like them. An LM317 under regular conditions is much more stable.

 

[Mr. Moscode]

Thanks for the 317HV info. I have had good luck with a TL783 with a TIP 50/MPSA42 Darlington piggy backed on a zener tied to the output in a closed circuit to regulate 500+ volts down to +350. It was used in the NYAudio Minuet and Minuet in A hybrid tube/fet preamp. I followed it with quad op amp secondary regulators for 4 very quiet 335V outputs.

I assumed that 48V was needed for phantom mic power. If so you would have a low chance of a short with 6.8K resistors feeding each mic. I would want it to be quieter than you get out a 317 anything. Op amp followers work really well.

 

[CJ]

mouser is out of 1 meg 1/4 watts, WTH?

 

[f.aiseur]

Ordered some at banzai two days ago :
http://www.banzaimusic.com/TL783CKC.html