Forums

Zeners in Series

Started by Cursitor Doom November 9, 2019
On 11/14/2019 5:09 PM, John Larkin wrote:
> On Thu, 14 Nov 2019 15:37:15 -0600, John S <Sophi.2@invalid.org> > wrote: > >> On 11/12/2019 11:41 AM, jlarkin@highlandsniptechnology.com wrote: >>> On Mon, 11 Nov 2019 21:37:34 -0800, Robert Baer >>> <robertbaer@localnet.com> wrote: >>> >>>> jlarkin@highlandsniptechnology.com wrote: >>>>> On Sun, 10 Nov 2019 14:34:38 -0800, Robert Baer >>>>> <robertbaer@localnet.com> wrote: >>>>> >>>>>> Cursitor Doom wrote: >>>>>>> On Sat, 09 Nov 2019 18:38:31 -0800, jlarkin wrote: >>>>>>> >>>>>>>> I even -gasp- sometimes use only half of a dual diode! >>>>>>>> >>>>>>>> But ridicule? Reputation? Who would know? >>>>>>> >>>>>>> Everyone here, now you've admitted to still using dual diodes! >>>>>>> :-D >>>>>>> >>>>>>> >>>>>>> >>>>>> Get out the swords, let's duel! >>>>> >>>>> Here's my programmable power supply for an extreme-UV (13 nm) >>>>> photodiode. It has a dual diode AND zeners in series. >>>>> >>>>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >>>>> >>>>> >>>>> Try to surrender with dignity. >>>>> >>>>> >>>>> >>>> Shouldn't C73, C77 be rated at least 500V? More like 1000V for safety? >>>> At least C64 is protected by R88 (pop). >>>> And....those BAV23S seem to be rated at a paltry 200V which will >>>> surely fry shorted. >>>> FURthermore, will that transformer withstand AC line voltage? >>>> >>>> Gurr. >>>> >>> >>> The voltage at TP15 is about +120. >>> >>> The input AC is high frequency, swiped from the main DC-DC converter >>> circuit. Here's the whole sheet: >>> >>> https://www.dropbox.com/s/cs1lhp7gslfs3e0/ESM_power.pdf?dl=0 >>> >>> We've sold about 3500 of these with roughly zero failures. >>> >> >> What does "roughly zero" mean? Is it zero or +/- SomethingLarge? > > We've got a few back that were mechanically mangled. There was a burst > of failures from one site caused by some outrageous ground loops that > incinerated some line drivers.
I guess that would be zero + a few. Whatever a few is. Certainly not zero.
> It's basically a 250 MHz, 12 bit ADC that integrates light pulse > energy and can acquire waveforms. > > https://www.dropbox.com/s/6equeg187v98xdu/ESM_PCB.jpg?raw=1 > > That switching power supply is an inch or so away from the ADC, and > noise is under 1 lsb RMS. >
On Sat, 16 Nov 2019 09:45:17 -0600, John S <Sophi.2@invalid.org>
wrote:

>On 11/14/2019 5:09 PM, John Larkin wrote: >> On Thu, 14 Nov 2019 15:37:15 -0600, John S <Sophi.2@invalid.org> >> wrote: >> >>> On 11/12/2019 11:41 AM, jlarkin@highlandsniptechnology.com wrote: >>>> On Mon, 11 Nov 2019 21:37:34 -0800, Robert Baer >>>> <robertbaer@localnet.com> wrote: >>>> >>>>> jlarkin@highlandsniptechnology.com wrote: >>>>>> On Sun, 10 Nov 2019 14:34:38 -0800, Robert Baer >>>>>> <robertbaer@localnet.com> wrote: >>>>>> >>>>>>> Cursitor Doom wrote: >>>>>>>> On Sat, 09 Nov 2019 18:38:31 -0800, jlarkin wrote: >>>>>>>> >>>>>>>>> I even -gasp- sometimes use only half of a dual diode! >>>>>>>>> >>>>>>>>> But ridicule? Reputation? Who would know? >>>>>>>> >>>>>>>> Everyone here, now you've admitted to still using dual diodes! >>>>>>>> :-D >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> Get out the swords, let's duel! >>>>>> >>>>>> Here's my programmable power supply for an extreme-UV (13 nm) >>>>>> photodiode. It has a dual diode AND zeners in series. >>>>>> >>>>>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >>>>>> >>>>>> >>>>>> Try to surrender with dignity. >>>>>> >>>>>> >>>>>> >>>>> Shouldn't C73, C77 be rated at least 500V? More like 1000V for safety? >>>>> At least C64 is protected by R88 (pop). >>>>> And....those BAV23S seem to be rated at a paltry 200V which will >>>>> surely fry shorted. >>>>> FURthermore, will that transformer withstand AC line voltage? >>>>> >>>>> Gurr. >>>>> >>>> >>>> The voltage at TP15 is about +120. >>>> >>>> The input AC is high frequency, swiped from the main DC-DC converter >>>> circuit. Here's the whole sheet: >>>> >>>> https://www.dropbox.com/s/cs1lhp7gslfs3e0/ESM_power.pdf?dl=0 >>>> >>>> We've sold about 3500 of these with roughly zero failures. >>>> >>> >>> What does "roughly zero" mean? Is it zero or +/- SomethingLarge? >> >> We've got a few back that were mechanically mangled. There was a burst >> of failures from one site caused by some outrageous ground loops that >> incinerated some line drivers. > > >I guess that would be zero + a few. Whatever a few is. Certainly not zero.
If a customer physically or electrically abuses a unit and breaks it, we don't consider that to be a failure. Neither does the customer. This customer is very serious about quality, and tracks failures and issues vendor scores. A failure here could cost megabucks. So we dispute "failures" that were field damage. -- John Larkin Highland Technology, Inc lunatic fringe electronics
On 11/16/2019 10:06 AM, jlarkin@highlandsniptechnology.com wrote:
> On Sat, 16 Nov 2019 09:45:17 -0600, John S <Sophi.2@invalid.org> > wrote: > >> On 11/14/2019 5:09 PM, John Larkin wrote: >>> On Thu, 14 Nov 2019 15:37:15 -0600, John S <Sophi.2@invalid.org> >>> wrote: >>> >>>> On 11/12/2019 11:41 AM, jlarkin@highlandsniptechnology.com wrote: >>>>> On Mon, 11 Nov 2019 21:37:34 -0800, Robert Baer >>>>> <robertbaer@localnet.com> wrote: >>>>> >>>>>> jlarkin@highlandsniptechnology.com wrote: >>>>>>> On Sun, 10 Nov 2019 14:34:38 -0800, Robert Baer >>>>>>> <robertbaer@localnet.com> wrote: >>>>>>> >>>>>>>> Cursitor Doom wrote: >>>>>>>>> On Sat, 09 Nov 2019 18:38:31 -0800, jlarkin wrote: >>>>>>>>> >>>>>>>>>> I even -gasp- sometimes use only half of a dual diode! >>>>>>>>>> >>>>>>>>>> But ridicule? Reputation? Who would know? >>>>>>>>> >>>>>>>>> Everyone here, now you've admitted to still using dual diodes! >>>>>>>>> :-D >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> Get out the swords, let's duel! >>>>>>> >>>>>>> Here's my programmable power supply for an extreme-UV (13 nm) >>>>>>> photodiode. It has a dual diode AND zeners in series. >>>>>>> >>>>>>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >>>>>>> >>>>>>> >>>>>>> Try to surrender with dignity. >>>>>>> >>>>>>> >>>>>>> >>>>>> Shouldn't C73, C77 be rated at least 500V? More like 1000V for safety? >>>>>> At least C64 is protected by R88 (pop). >>>>>> And....those BAV23S seem to be rated at a paltry 200V which will >>>>>> surely fry shorted. >>>>>> FURthermore, will that transformer withstand AC line voltage? >>>>>> >>>>>> Gurr. >>>>>> >>>>> >>>>> The voltage at TP15 is about +120. >>>>> >>>>> The input AC is high frequency, swiped from the main DC-DC converter >>>>> circuit. Here's the whole sheet: >>>>> >>>>> https://www.dropbox.com/s/cs1lhp7gslfs3e0/ESM_power.pdf?dl=0 >>>>> >>>>> We've sold about 3500 of these with roughly zero failures. >>>>> >>>> >>>> What does "roughly zero" mean? Is it zero or +/- SomethingLarge? >>> >>> We've got a few back that were mechanically mangled. There was a burst >>> of failures from one site caused by some outrageous ground loops that >>> incinerated some line drivers. >> >> >> I guess that would be zero + a few. Whatever a few is. Certainly not zero. > > If a customer physically or electrically abuses a unit and breaks it, > we don't consider that to be a failure. Neither does the customer. > > This customer is very serious about quality, and tracks failures and > issues vendor scores. A failure here could cost megabucks. So we > dispute "failures" that were field damage. >
Okay. That makes sense.
On Sunday, November 10, 2019 at 6:17:06 PM UTC-5,  jlarkin wrote:
> > Here's my programmable power supply for an extreme-UV (13 nm) > photodiode. It has a dual diode AND zeners in series. > > https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1
What do you think about the Bel 2798D 16 Pin SMD ISDN Transformer? I have about 2500 of them, in storage. I need to build some clean 90-100VDC power supplies for old battery powered tube portable radios. https://www.dropbox.com/s/dxn3bh8uha5ov4c/Bel%202798D.pdf?dl=0
On Mon, 18 Nov 2019 00:02:56 -0800 (PST), Michael Terrell
<terrell.michael.a@gmail.com> wrote:

>On Sunday, November 10, 2019 at 6:17:06 PM UTC-5, jlarkin wrote: >> >> Here's my programmable power supply for an extreme-UV (13 nm) >> photodiode. It has a dual diode AND zeners in series. >> >> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 > > >What do you think about the Bel 2798D 16 Pin SMD ISDN Transformer? I have about 2500 of them, in storage. I need to build some clean 90-100VDC power supplies for old battery powered tube portable radios. > >https://www.dropbox.com/s/dxn3bh8uha5ov4c/Bel%202798D.pdf?dl=0
How much power do you need? I guess a battery powered radio doesn't need much B+. You'd need to run the frequency up to avoid saturation, so there could be an EMI issue. Maybe use a doubler or C-W multiplier to allow keeping the frequency down. -- John Larkin Highland Technology, Inc lunatic fringe electronics
>On Mon, 18 Nov 2019 00:02:56 -0800 (PST), Michael Terrell ><terrell.michael.a@gmail.com> wrote: > >>On Sunday, November 10, 2019 at 6:17:06 PM UTC-5, jlarkin wrote: >>> >>> Here's my programmable power supply for an extreme-UV (13 nm) >>> photodiode. It has a dual diode AND zeners in series. >>> >>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >> >> >>What do you think about the Bel 2798D 16 Pin SMD ISDN Transformer? I have about 2500 of them, in storage. I need to build some >>clean 90-100VDC power supplies for old battery powered tube portable radios. >> >>https://www.dropbox.com/s/dxn3bh8uha5ov4c/Bel%202798D.pdf?dl=0 > >How much power do you need? > >I guess a battery powered radio doesn't need much B+. > >You'd need to run the frequency up to avoid saturation, so there could >be an EMI issue. Maybe use a doubler or C-W multiplier to allow >keeping the frequency down.
What is so difficult about using a ferrite E core and just 2 x 12 turns? For a bit of battery based tube radio of the old days, say a DL92 output stage, you need about 100 mA, plus the rest of the tubes say 200 mA at 90 V. https://www.radiomuseum.org/tubes/tube_dl92.html You also need 1.4 V for the heaters (down convert). Even a 1 transistor blocking oscillator or 1 transistor driven by a 555 timer would work. then a 1:2 turns ratio can give you 140V or so from 12V in. One extra turn for the heater,,, Use about 1 turn per volt. Or 2 transistors with voltage stabilizing feedback, repaired just such a thing a week or so ago. For things like one-off just keep some small ferrite E cores and some wire in stock. Yes frequency should be above audio ;-), say 15 kHz or higher.
On Mon, 18 Nov 2019 15:46:40 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

>>On Mon, 18 Nov 2019 00:02:56 -0800 (PST), Michael Terrell >><terrell.michael.a@gmail.com> wrote: >> >>>On Sunday, November 10, 2019 at 6:17:06 PM UTC-5, jlarkin wrote: >>>> >>>> Here's my programmable power supply for an extreme-UV (13 nm) >>>> photodiode. It has a dual diode AND zeners in series. >>>> >>>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >>> >>> >>>What do you think about the Bel 2798D 16 Pin SMD ISDN Transformer? I have about 2500 of them, in storage. I need to build some >>>clean 90-100VDC power supplies for old battery powered tube portable radios. >>> >>>https://www.dropbox.com/s/dxn3bh8uha5ov4c/Bel%202798D.pdf?dl=0 >> >>How much power do you need? >> >>I guess a battery powered radio doesn't need much B+. >> >>You'd need to run the frequency up to avoid saturation, so there could >>be an EMI issue. Maybe use a doubler or C-W multiplier to allow >>keeping the frequency down. > >What is so difficult about using a ferrite E core and just 2 x 12 turns?
He doesn't have 2500 of them! -- John Larkin Highland Technology, Inc lunatic fringe electronics
>On Mon, 18 Nov 2019 15:46:40 GMT, Jan Panteltje ><pNaOnStPeAlMtje@yahoo.com> wrote: > >>>On Mon, 18 Nov 2019 00:02:56 -0800 (PST), Michael Terrell >>><terrell.michael.a@gmail.com> wrote: >>> >>>>On Sunday, November 10, 2019 at 6:17:06 PM UTC-5, jlarkin wrote: >>>>> >>>>> Here's my programmable power supply for an extreme-UV (13 nm) >>>>> photodiode. It has a dual diode AND zeners in series. >>>>> >>>>> https://www.dropbox.com/s/9e2ojyx0beflcaq/ESM_PD_Supply.jpg?raw=1 >>>> >>>> >>>>What do you think about the Bel 2798D 16 Pin SMD ISDN Transformer? I have about 2500 of them, in storage. I need to build >>>>some >>>>clean 90-100VDC power supplies for old battery powered tube portable radios. >>>> >>>>https://www.dropbox.com/s/dxn3bh8uha5ov4c/Bel%202798D.pdf?dl=0 >>> >>>How much power do you need? >>> >>>I guess a battery powered radio doesn't need much B+. >>> >>>You'd need to run the frequency up to avoid saturation, so there could >>>be an EMI issue. Maybe use a doubler or C-W multiplier to allow >>>keeping the frequency down. >> >>What is so difficult about using a ferrite E core and just 2 x 12 turns? > >He doesn't have 2500 of them!
He does not have 2500 radios either! Why compromise?
On Saturday, November 9, 2019 at 6:38:41 PM UTC-8, jla...@highlandsniptechnology.com wrote:

> I sometimes put resistors or caps in series or parallel, to avoid > adding another line to the BOM of a board, even if all the right > values are in stock. Saves loading up a reel on the pick-and-place to > slam down one cheap part.
IIRC, our Production gives a rule-of-thumb estimate of $0.27 to take a part reel out of the stockroom and put it on a feeder (to load the first part). That's an estimate per board, so some assumptions not given here are obviously embedded in that estimate. And the cost can, in some cases, be multiplied by 2 for a two-sided board.
On Mon, 18 Nov 2019 11:33:49 -0800 (PST), Simon S Aysdie
<gwhite@ti.com> wrote:

>On Saturday, November 9, 2019 at 6:38:41 PM UTC-8, jla...@highlandsniptechnology.com wrote: > >> I sometimes put resistors or caps in series or parallel, to avoid >> adding another line to the BOM of a board, even if all the right >> values are in stock. Saves loading up a reel on the pick-and-place to >> slam down one cheap part. > >IIRC, our Production gives a rule-of-thumb estimate of $0.27 to take a part reel out of the stockroom and put it on a feeder (to load the first part). That's an estimate per board, so some assumptions not given here are obviously embedded in that estimate. > >And the cost can, in some cases, be multiplied by 2 for a two-sided board.
I'd expect that our cost is a lot higher. After the run is done, we count the parts on each reel, with our new x-ray machine, and then put the partial reel back in stock. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com