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What happend to 320K resistors ?
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floobydust:

--- Quote from: ogden on February 20, 2021, 11:03:21 pm ---
--- Quote from: floobydust on February 20, 2021, 08:44:31 pm ---The EE generation following us can't use a breadboard anymore, they are obsolete. Through-hole is dying out it was King for experimenting and learning electronics.

--- End quote ---

It's like saying that computer music will obsolete piano play and 3d printers will obsolete LEGO :) Just one of many examples why breadboard is far from dying and next generations will use such or alike:

https://www.amazon.com/s?k=arduino+starter+kit

--- End quote ---

The piano is getting smaller every day but our fingers are the same size. It's the workability of SMT that make it difficult and new parts are not offered in anything but through-hole, for years now.
coppercone2:
and.. probes cost how much? Dip clip, wonderful. You can do soic but its a little janky, but any resistor or whatever is a total pain in the ass requiring new equipment that takes up alot of room (positioning arms etc)
ogden:

--- Quote from: srb1954 on February 21, 2021, 01:09:57 am ---The advantage of using leaded components in these situations is that the component manufacturer has already done most of the thermal engineering work for you.

--- End quote ---

Your claim is true for leaded resistors up-to certain power level only. Show me "already done thermal enginering" of this 35W through-hole resistor: PWR220T-35-50R0J  It is not fault of SMT resistor that some can't do thermal engineering ;) If you actually look for it, you can find pre-existing thermal engineering (appnotes) for SMT power resistors. Just an example:  https://www.vishay.com/docs/53047/pra-appn.pdf, https://www.vishay.com/docs/53048/pprachp.pdf


--- Quote ---If your circuitry using using fast pulse waveforms then you have to be very concerned about unequal voltage sharing across a string of resistors due to circuit parasitic capacitances and inductances. In some cases you even have to put balancing capacitors across each resistor to force equal sharing of pulse voltages. This requires extra engineering time not to mention the extra cost of additional BOM items, assembly and test time and additional PCB area.

Again, using a single leaded part is often a much better solution.

--- End quote ---

Just search and you will find 10KV SMT resistors. Even precision low TC parts if needed. Argument could be price, but not as you say "use leaded parts. period." :D

Fact that you can think of >1KV edge case where even leaded components require careful engineering does not prove your initial blanket statement. Most of applications where one shall start to think about SMT resistor voltage rating and chaining are AC mains. SMT resistors are fine and widely used in such.
ogden:

--- Quote from: floobydust on February 21, 2021, 05:35:41 am ---The piano is getting smaller every day but our fingers are the same size. It's the workability of SMT that make it difficult and new parts are not offered in anything but through-hole, for years now.

--- End quote ---

If you want to use modern, highly integrated ICs then be ready to face consequences. When you introduce modern IC, you have to introduce modern way of engineering too. Other option - use old parts or 3rd party DIP conversion adapters/modules.
GlennSprigg:
All this reminds me of my Security Systems days, where there are EOL (End Of Line) Resistors, next to
the field sensors / reed switches etc., and the electronic control system needed to  see a VERY specific
resistive value, that was not only uncommon, (like 273k or what ever, made up!), but very difficult to even simulate
with a bunch of series/parallel resistors!   8)
Most (lazy) installers often put them in the control panel!! so totally negating their use!!   >:(

For interest... All higher level systems (Govt places, prisons etc.) utilize a "1-pair-in-the-world" IC Chip
epoxy-moulded into the field 'sensor/etc), and the other sole matching IC in the master control panel,
just for that individual zone/sector.  There's no way to fool them in the field!!   ;D
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