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Microcontrollers / Re: How to Interface 108 Thermistors with Arduino
« Last post by mino-fm on Today at 05:12:42 pm »
Unfortunately, the ATmega328 only provides a 1.1Vref which is 0.55mA to the sensor

PB.0 is used as output to supply the sensor dividers. Vref is input and supplied by PB.0 output too, maybe 4.5 V.
As told before, today I would use a controller with 12 bit ADC still not knowing what is really needed.
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An important detail of those efficiencies is that they only apply when the converter is working in continuous mode. In disc mode eff goes down, but sometimes it is necessary to operate in that area due to the low load power requirement

Yeah I noticed that in many switching I.C datasheets, as the current output goes down, the efficiency significantly worsens, sometimes below 50%.

There's no practical use-case for me to look into this at this time, but I have been curious about whether there are switching I.C's which remain 80%+ efficiency across a wide current range (ex. 1mA-5A). Maybe this just isn't possible however, due to the associated components of the switching regulator (I'm thinking the inductors + resistors would greatly influence the efficiency at lower currents). Anyway lol

This is a somewhat rare requirement with some exceptions.  The chip companies make whatever customers need.  The MAX797 is a third generatioin synch buck that did pretty well in this respect.

The exception, eluded to above is when uP's sleep etc.  Mentioned elsewhere, modern power supplies often go into PFM or skipping modes to maintain efficiencies at light loads.  The difficulty of these non continuous modes is ripple and noise. 

The other thing to wrap your head around is to realize that efficiency isn't so important at light loads, its in the medium and heavy current regimes of operation.  If you're 20% efficient at 1 mA, this is much less important efficiencies much less 90 at heavy loads.  Notebooks use a linear regulator in deep sleep modes.(they don't put coin cells in notebooks anymore).  Of course, there are exceptions, if your whole life is light load except one mode where you're heavy.  In this case, you make the supply to have peak efficiency at  lower currents and not do so hot at high outputs.  Its all engineerging and optimazation.
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Thermal Imaging / Re: FLIR TG 297 Frozen on logo screen
« Last post by thermionic_emission on Today at 05:12:30 pm »
Thanks for your reply.
I am comfortable opening up electronics and have some engineering background to give it a non destructive try .
I had ofcourse disassembled it to do the battery related efforts.
However, I dont see a serial port like what I see in this videohttps://www.youtube.com/watch?v=zcuPbNl0wjg] [url]https://www.youtube.com/watch?v=zcuPbNl0wjg
[/url]

I see an unpopulated section which says JTAG, i presume i need to populate this with some connector?
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For me AI is not what it says on the box. As far as I am concerned it searches through knowledge bases - often of dubious quality - available in the internet and spews out the most probable "answer". This has nothing to do with intelligence. Even worse, it cannot say "I simply don't know". Surely this is only the beginning and things will improve over the years.
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there still might be some commonality between the two things since they are both trying to couple energy into a waveguide

Reading the intro to the special tubes section of one of the documents, I wonder about using a laser to heat up gas in a wave guide too

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Beginners / Re: Special double relay needed
« Last post by kripton2035 on Today at 05:02:01 pm »
a Pi is completely overkill for that... a small pic or atmel chip is plenty sufficient.
a PLC is completely overpriced.

or even this
https://www.aliexpress.com/item/1005006053150372.html

and don't forget you have to make the device "automotive compliant" that is completely waterproof and vibrationproof.
this could be the most difficult part of the project !
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and why boosting voltages is rarely done in mobile applications)
If true, I'd wager it's because most modern mobile electronics make use of lithium batteries (3.7-4.2V), whereas all the circuitry they're powering (except maybe the display) uses lower voltages (1-3.3V). Nothing to do with power efficiency, that's for sure.

>>>
I don't know how far you go back but before we had all this single cell PA stuff, phones ran on a 2S stack or 6 NiCd Stack used bucks.  The PA ran off the battery and logic volts were bucked down.  These could have used a boost but it was messy.  Things like 2 way pagers of the day used boosts but used enormous caps to help send the bursty data when required- almost like a photoflash application.  The other problem with boosts is that the filter is harder (cap esr demands).  If you're powering a PA, that all turns into AM type noise with ugly sidebands, etc.



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An important detail of those efficiencies is that they only apply when the converter is working in continuous mode. In disc mode eff goes down, but sometimes it is necessary to operate in that area due to the low load power requirement

Yeah I noticed that in many switching I.C datasheets, as the current output goes down, the efficiency significantly worsens, sometimes below 50%.

There's no practical use-case for me to look into this at this time, but I have been curious about whether there are switching I.C's which remain 80%+ efficiency across a wide current range (ex. 1mA-5A). Maybe this just isn't possible however, due to the associated components of the switching regulator (I'm thinking the inductors + resistors would greatly influence the efficiency at lower currents). Anyway lol
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If you like, I can make closer picture of the CRT + driver, each are matched with the same number. They each came from the same TDS oscilloscope so the PCB has printed specific number exactly the same as the sticker on the CRT. The origin of the mono-chrome unit are respectively from a one TDS510A, two TDS540C, two TDS520D.

About shipping from France to Japan, I'm not really in the know or expert of logistics about cost but if you have special deals or knowledge or suggestion including the insurance aspect, it would easier for me.

I still have main CPU board unit to test each CRT (the CRT/PCB set be tested the running TDS linked through J5 connector and shared ground to chassis) so I can choose the one with more intensity prior shipping to Japan.
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Specialisation had been ongoing since the time of Thomas Young

https://en.wikipedia.org/wiki/The_Last_Man_Who_Knew_Everything
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