18:28 <d1b2> <tnt> https://www.tme.eu/en/details/ldcl015mr/ldo-regulated-voltage-regulators/stmicroelectronics/?utm_source=octopart.com&utm_medium=cpc&utm_campaign=compare-2022-02

19:20 <d1b2> <esden> Thanks @tnt got them. Let's see if they will work for us. 🤞

19:21 <d1b2> <tnt> "Stock level: 0pcs". Ah wow, you really took all of them 😅

19:21 <d1b2> <esden> look... desperate times require desperate measures

19:22 <d1b2> <esden> It is a gamble... let's hope it pays off :/

19:23 <d1b2> <esden> (I would be really angry if I got only a few units, tested them, they worked, and I could not get more)

19:23 <d1b2> <esden> (it is still not the 8k pcs we need, but it is getting us closer)

19:52 <whitequark> let's see how it works out!

19:53 <SnoopJ> 🙏

20:21 <ar> how many were there?

20:23 <d1b2> <esden> bit over 2.5k

20:25 <electronic_eel> @esden i'm looking forward to testing of them. do you want to do live testing in a stream?

20:28 <d1b2> <esden> I don't have a test plan yet. I just jumped on them as they were available, seems close enough replacement, and the price was better than what I have seen otherwise.

20:29 <d1b2> <davidc__> There are another 564 at newark

20:29 <d1b2> <esden> We need to put together a test protocol. (and yes I am happy to send you some parts when I get them @electronic_eel )

20:29 <d1b2> <davidc__> https://canada.newark.com/stmicroelectronics/ldcl015mr/ldo-adj-150ma-0-15a-40-to-125deg/dp/86W0470?CMP=AFC-SF-BNL

20:29 <d1b2> <esden> @davidc__ too expensive

20:30 <d1b2> <davidc__> Fair enough!

20:30 <whitequark> is it a drop-in replacement, or does it need a PCB revision?

20:31 <d1b2> <esden> that is an ongoing problem with these parts, "burst of excitement for a small batch of the part" -> then either "dang someone was faster than me" or "shit too pricy"

20:31 <d1b2> <esden> @whitequark I have not checked yet

20:32 <d1b2> <esden> (I assumed if it needs a pinout change it is still "acceptable")

20:33 <davidc__> Looks to be pin-compatible from a skim of the datasheet

20:34 <davidc__> Vref is different - 0.8v for the ST part, 1.2V for the TI part

20:35 <electronic_eel> yeah, the different vref then needs different resistors on the dac or a different firmware (or maybe both)

20:35 <d1b2> <esden> ok, that is still in the realm "we can deal with this"

20:36 <electronic_eel> i would say so

20:36 <d1b2> <esden> replacing the resistors would make it easier on the firmware compatibility, so I think I would rather do that

20:36 <d1b2> <esden> if we can ...

20:40 <electronic_eel> even if it is just changed resistors, we should somehow mark the units that use this setup. so that it is easy for a user to find out which kind of unit they got, for example when some problem shows up or if they want to tinker with their glasgow

20:41 <electronic_eel> not everyone has microscope lighting like this to easily read the part markings: https://twitter.com/azonenberg/status/1494061604161220615

20:45 <d1b2> <esden> Ohh yes, I will definitely mark the boards. Probably in the serial number field or something.

20:46 <d1b2> <esden> (I had the same thought 😉 )

20:46 <d1b2> <esden> now I wish KiCad already had alternate population options sigh

21:05 <d1b2> <esden> ok. there is an issue for that, there is some effort in that direction, and there are some scripts that implement some of it https://gitlab.com/kicad/code/kicad/-/issues/2131

21:08 <davidc__> I'm fairly sure we can just change R27 to account for the difference in VFB

21:09 <davidc__> but let me double check my math

21:28 <d1b2> <esden> @davidc__ thank you 🙂 👍

21:38 <davidc__> esden: according to my unchecked math, keeping R28/R29 and changing R27 to 16.91 k will have the same VDAC = VIO curve

21:38 <davidc__> Now, 16.91 isn't a 1% tolerance value; I've gotta work out the tolerancing - but presumably this is something that needs cal anyways (or we have an acceptable error)

21:39 <d1b2> <esden> Ok cool, making a note of that. We probably should start an issue on github for this.

21:39 <davidc__> er, keep the VDAC _to_ VIO curve the same

21:39 <davidc__> That will also increase the current out of the DAC; that needs to be checked too

22:01 <davidc__> esden: assuming that works, is that the last missing piece for the first batch?

22:05 <d1b2> <esden> Lattice despite promising to expedite shipment are dragging their feet. So I need to follow up on that. And we need to look in alternate footprint for the rail VREGs so I can use the different packaged fixed regulators. I think that is pretty much it.

22:07 <d1b2> <esden> to be honest, the expedited shipping from lattice needs big fat quotemarks on it ...