Author Topic: Group-buy for 10V LTZ1000A reference? [Completed, no more boards]. (Read 24824 times)

TiN · « **Reply #25 on:** January 23, 2018, 04:18:09 am »

Got quote from VPG resistors (13/1K network hermetic, 120R hermetic, 70K epoxy).
However lead-time is looking around 11-16 weeks, which makes it around May'18.

If anyone want to drop off waiting that long, let me know.

Pipelie · « **Reply #26 on:** January 24, 2018, 01:44:19 am »

Quote from: TiN on January 23, 2018, 04:18:09 am

Got quote from VPG resistors (13/1K network hermetic, 120R hermetic, 70K epoxy).
However lead-time is looking around 11-16 weeks, which makes it around May'18.

If anyone want to drop off waiting that long, let me know.

the lead-time of VPG resistors easily goes around 16-18 weeks

, we ordered several times from Vishay in the past 3 years.

ramon · « **Reply #27 on:** January 24, 2018, 02:43:27 pm »

Hi Tin! What is the price for the 13/1K hermetic resistor network? I am thinking about building two LTZ1000 boards .... someday. So I can wait.

TiN · « **Reply #28 on:** January 24, 2018, 04:32:26 pm »

It's around $70ish so far.

Kleinstein · « **Reply #29 on:** January 24, 2018, 04:44:16 pm »

For a 10 V reference the 13K/1 K divider at the LTZ1000 is not that important. The divider for the 7 V to 10 V step is way more important (e.g. about by a factor of 50). It would only be for an possible 7 V output that the stability of the temperature set point can matter. There is a kind of natural limit on how much to spend on the resistors - at some point it would be more effective to have a second ref. chip or a way to measure the voltage at the 13K/1 K divider - possibly to make it an extra 0.4xx V reference output.

cellularmitosis · « **Reply #30 on:** January 24, 2018, 06:51:39 pm »

Quote from: TiN on January 24, 2018, 04:32:26 pm

It's around $70ish so far.

The VHD200 12.5/1K divider I ordered from Texas Components was $46.

Edit: lead time is 3 weeks. should be here by 1/29.

chriswebb · « **Reply #31 on:** January 24, 2018, 08:16:03 pm »

Is there anything you need from me to get my order confirmed? Payment sent or something? I think I missed when you were getting the orders confirmed.

TiN · « **Reply #32 on:** January 25, 2018, 01:08:22 am »

Naw, you all good. Just sanity check for myself.

1anX · « **Reply #33 on:** January 25, 2018, 01:32:52 am »

A little off topic but how well does a AD584KH compare used in temp controlled (aircoditioned) lab?
LiPo battery powered versions are readily available https://www.ebay.com/itm/High-Precision-4-Channel-2-5-7-5-5-10V-Voltage-Reference-Module-AD584KH-NEW-coi/202035834876?hash=item2f0a462ffc:g:4D0AAOSw0ThZoOBg
Would this be a waste of money to use to check calibration of lab equipment?

Update: I did a forum search and found my answer! http://www.markhennessy.co.uk/ad584_references/

Jxw6637 · « **Reply #34 on:** January 28, 2018, 10:32:07 pm »

I am interested in getting one, is there an extra?

TiN · « **Reply #35 on:** January 30, 2018, 04:09:01 am »

Sorry, no more PCBs on this project.

TiN · « **Reply #36 on:** June 09, 2018, 01:58:25 pm »

Yay, finally something arrived.

70K resistors will be used in above-mentioned FX 10pcs run. 1K/13K VHP203T's are just for temporary testing, final boards will have 1/13K VHD divider instead.
Rest of resistors (120R, divider) expected to arrive next month.

Resistors were ordered February 7, 2018, so this gives us ~17 week delivery time for these and ~20weeks or so for remaining.

Started tempco test already.

ManateeMafia · « **Reply #37 on:** June 09, 2018, 02:04:53 pm »

you need more 3458A

johartley2001 · « **Reply #38 on:** June 19, 2018, 12:05:10 pm »

are these still available to buy ?

TiN · « **Reply #39 on:** June 19, 2018, 12:41:07 pm »

All FX units are allocated for members, and I'm still waiting for final part delivery - resistors. It is typical to have 17-24 weeks lead time order for precision resistors.

Perhaps somebody on EEVBlog have another LTZ reference to sell.

eurofox · « **Reply #40 on:** June 19, 2018, 01:04:43 pm »

Quote from: johartley2001 on June 19, 2018, 12:05:10 pm

are these still available to buy ?

Build one yourself, there is enough information in this thread to do it.

Mine in aging right now and start to be very stable, it include a 10V buffer, it is mounted in a teco box and I will add a oven control on it to bring the temperature to 35°C +/- 0;1° C.

In fact I build different versions most without buffer to 10V.

Only problem is final calibration

SKPang · « **Reply #41 on:** June 28, 2018, 09:02:42 am »

Hi TiN,

Are you going to do another batch ? If so put me down for one.

TiN · « **Reply #42 on:** June 28, 2018, 12:23:13 pm »

Nope, due to high cost only 14pcs of these modules will exist in the world, sorry.

KX one is available on OSH Park for PCBs : https://oshpark.com/shared_projects/HfKcqjV3
(LTZ chips you can buy from ADI and resistors from Edwin Pettis here or VPG).

TiN · « **Reply #43 on:** August 08, 2018, 09:33:02 pm »

After 181 days of waiting, complete VPG order is finally here.

Now I can go ahead and build stuff!

Vgkid · « **Reply #44 on:** August 09, 2018, 03:30:49 am »

Damn , all of those resistors cost more than everything I have bought in my lab...

TiN · « **Reply #45 on:** August 13, 2018, 12:29:53 pm »

Okay, Digikey box from USA arrived nice and safe.

Wait is over, we are finally ready to start assembly. Enjoy, that's 6K+ in parts...

Zucca · « **Reply #46 on:** August 13, 2018, 12:45:47 pm »

TiN · « **Reply #47 on:** August 14, 2018, 04:10:48 pm »

Got some parts for low-noise regulators assembled.

Close-up.

TiN · « **Reply #48 on:** August 16, 2018, 06:37:42 pm »

Had little chance to work on assembly tonight.

LDO regulators on 5 boards are good and quiet, now putting in LTZ section parts (except BMF resistors and LTZ itself, obviously) and output stage parts.

BMF resistors are still going thru sorting/binning so it will take some time till i get overall result table to pre-sort those before installing into boards permanently.

branadic · « **Reply #49 on:** August 16, 2018, 06:48:31 pm »

The ceramic caps are quite a bit big for the footprint, aren't they?

-branadic-


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Author Topic: Group-buy for 10V LTZ1000A reference? [Completed, no more boards]. (Read 24824 times)

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