Empathy List Archives

DD

Dr. David Kirkby

Wed, Apr 11, 2018 11:47 AM

There seems to be plenty of evidence that meters like the 3458A improve
stability over time. I believe that most/all is due to improved stability
of the LTZ1000A.

Does anyone know if desoldering one and resoldering resets the aging
process? I see a number of used LTZ1000A ICs on eBay from China that look
like they have been poorly removed. They are about the same price as a
brand new LTZ1000A.

I wondering if properly removed, a used chip is no more stable than a new
one.

Dave

There seems to be plenty of evidence that meters like the 3458A improve stability over time. I believe that most/all is due to improved stability of the LTZ1000A. Does anyone know if desoldering one and resoldering resets the aging process? I see a number of used LTZ1000A ICs on eBay from China that look like they have been poorly removed. They are about the same price as a brand new LTZ1000A. I wondering if properly removed, a used chip is no more stable than a new one. Dave

PK

Poul-Henning Kamp

Wed, Apr 11, 2018 11:58 AM

In message CANX10hD3-XS0NKq38vj5ycTAT1hkDsqumvLP+anm9-+--6y9wg@mail.gmail.com
, "Dr. David Kirkby" writes:

Does anyone know if desoldering one and resoldering resets the aging
process?

I don't think it "resets" as such, but it certainly starts some kind
of aging process, as does hard knocks, thermal shocks, vibration, ...

--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

-------- In message <CANX10hD3-XS0NKq38vj5ycTAT1hkDsqumvLP+anm9-+--6y9wg@mail.gmail.com> , "Dr. David Kirkby" writes: >Does anyone know if desoldering one and resoldering resets the aging >process? I don't think it "resets" as such, but it certainly starts some kind of aging process, as does hard knocks, thermal shocks, vibration, ... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

AJ

Andreas Jahn

Wed, Apr 11, 2018 7:10 PM

Hello,

when I have a "accident" from my unbuffered LTZ-references by shorting
the output (for a very short time),
(so setting the temperature setpoint to infinite and thus the heater
cirquit goes to maximum output)
I usually have a large shift on the device. (several ppms).

A part of the shift can be cured by power cycling (cooling down and
heating up to normal operating temperature).
The remaining shift (-2 .. -5 ppm usually) is permanently on the device.
After such a event I usually have around 6 months increased ageing rate
until it goes back to the normal -1 .. -2ppm/a

with best regards

Andreas

Am 11.04.2018 um 13:58 schrieb Poul-Henning Kamp:

In message CANX10hD3-XS0NKq38vj5ycTAT1hkDsqumvLP+anm9-+--6y9wg@mail.gmail.com
, "Dr. David Kirkby" writes:

Does anyone know if desoldering one and resoldering resets the aging
process?

I don't think it "resets" as such, but it certainly starts some kind
of aging process, as does hard knocks, thermal shocks, vibration, ...

Hello, when I have a "accident" from my unbuffered LTZ-references by shorting the output (for a very short time), (so setting the temperature setpoint to infinite and thus the heater cirquit goes to maximum output) I usually have a large shift on the device. (several ppms). A part of the shift can be cured by power cycling (cooling down and heating up to normal operating temperature). The remaining shift (-2 .. -5 ppm usually) is permanently on the device. After such a event I usually have around 6 months increased ageing rate until it goes back to the normal -1 .. -2ppm/a with best regards Andreas Am 11.04.2018 um 13:58 schrieb Poul-Henning Kamp: > -------- > In message <CANX10hD3-XS0NKq38vj5ycTAT1hkDsqumvLP+anm9-+--6y9wg@mail.gmail.com> > , "Dr. David Kirkby" writes: > >> Does anyone know if desoldering one and resoldering resets the aging >> process? > I don't think it "resets" as such, but it certainly starts some kind > of aging process, as does hard knocks, thermal shocks, vibration, ... > >

volt-nuts@lists.febo.com

Does desoldering and resoldering an LTZ1000A reset the ageing?