whats your most hated component

[Terry Bites]

Whats your most hated component?
Suggestions please.

[WIMPy]

Whats your most hated component?

The one that failed and took others with it in doing so.

[Manul]

EE psychotherapy session

Blue LED.

[nonius_]

RIFA and WIMA paper capacitors are pretty high on my hate-list....

[fchk]

Packages with no silicon inside when the wife of the boss purchased the parts on the grocery market in Shenzhen.
Seen more then once.

[Zero999]

Domestic mains sockets. The way they're daisy chained together. They should have three push fit terminals per conductor, to avoid the need to shove up to thee conductors into a crappy screw terminal.

[jpanhalt]

Unlabeled components of which ceramic SMD capacitors are high on the list.  I don't hate them.  They're just annoying.

[MisterHeadache]

The unobtainium component.

You know, when you run across a cool project design from a few years (decades) ago, get really pumped up to build one, then find that it was designed around a transistor/MOSFET/IC that went out of production years ago and has no modern replacement.

[themadhippy]

They should have three push fit terminals per conductor

likes the mk rapid fix?
https://buildings.honeywell.com/gb/en/brands/our-brands/mk-electric/products/logic-plus-rapid-fix

[srb1954]

Any component not having a proper datasheet.

[bookaboo]

Anything to do with household mains wiring. Sadists.

[Andy Chee]

Parasitic components

[IDEngineer]

As a category: Connectors.

Expensive to buy, labor intensive (meaning expensive) to assemble/install, usually the least reliable component, often single sourced/unique so out of stock or hard to find, the list is endless.

Hardly a week goes by that I don't get an opportunity to mention how much I hate connectors. No other class of components comes anywhere close.

[bdunham7]

The shorted tantalum dip capacitor...

[mawyatt]

Selenium Rectifiers!!

Best

[ArdWar]

Ferrite beads, especially those in chip scale form factor.

Not the component itself per se, but more about how the manufacturers market it. There's hardly any useful information on their datasheets.
For example saturation current should be specified front and center. It fundamentally important in how they behave in a circuit. Yet none that I know actually put the numbers in, meanwhile thermal/DCR current is the one advertised in big letters.
Frequency response? lol a single RZX chart is all you get, if they even bother to put one for each SKU instead of "general characteristics" for the entire series.

[perdrix]

Ferrite beads, especially those in chip scale form factor.

Not the component itself per se, but more about how the manufacturers market it. There's hardly any useful information on their datasheets.
For example saturation current should be specified front and center. It fundamentally important in how they behave in a circuit. Yet none that I know actually put the numbers in, meanwhile thermal/DCR current is the one advertised in big letters.
Frequency response? lol a single RZX chart is all you get, if they even bother to put one for each SKU instead of "general characteristics" for the entire series.

Totally agree!

David

[mtwieg]

Parasitic components

Hate it when these get backordered. Gotta have my puffs....

[hans]

BH1730FVC

Its the only part where I ordered a pack of 5, and I failed to solder any onto a PCB in a working state.
The problem: its a transparent IC package, 1.6x3mm size, 0.5mm pitch, where is pin 1? Its a "TINY" stripe on the top side of the package. Good luck seeing that behind a clear IC package.
And is the bottom side assymetrical or marked as on all LEDs?? Nah! That would have been too easy.

I actually got a batch of sensor boards made by JLC and there is nothing wrong electrically with the chip. Its just these transparant packages that are the absolute worst! And I say that by handsoldering 0201s/0402s without magnification and hotair soldering small BGAs with "just do it" mentality -- 3 HyperRAM boards assembled, 3 working units, zero paste, zero preheater, zero experience.

Maybe I can succeed now that I've a microscope. But I don't even feel like trying again

[JacobPilsen]

555

[pcprogrammer]

Not so much a single component, but more an ic package type. QFN in whatever size there is.

Difficult to solder and confirm that the connections are made as intended. When the board is not working it is just a guess as to what the problem is. Is there a short somewhere, or is there no connection to the pcb on some pins, did the ic die while soldering with hot air. 

I will avoid them as much as possible.

[jbb]

An unnamed secure microcontroller which:

- had a coin cell Vbat pin for secure battery backup RAM and real time clock

- wouldn’t reliably boot for first time programming if you applied main power and Vbat simultaneously. You needed to apply Vbat first. Totally undocumented

- had another special supply pin, which initial datasets said to connect to a particular supply. Turns out that under some conditions that could corrupt the battery backup RAM. Later data sheets just said ‘connect to ground.’  No errata issued. No warning.

[Sensorcat]

The battery that leaks before it is halfway discharged and before it has reached its expiration date.

[temperance]

Op amps in SOT/SC/DFN packages with at least five different pin layouts for each package variant. You always get the wrong one.
Single gate logic available in 15 different packages. You always get the wrong one.
LDO's in at least 5 different packages with for each package three or four different pin arrangements. You always get the wrong one.
Osram 1206, 0805 and 0603 LED's. Most of them have the marking on the correct side except for some of them. You're fucked anyhow and have to go and find a data sheet because was it the amber one with the wrong marking or the green one or perhaps the red one? Banned forever.
Some Infineon MOSFET driver which is pin compatible with a version from On semi and TI. The ON and TI are the same thing. The Infineon part specifies a maximum input voltage of 5 V for the control inputs where the On and TI variant can work fine with up to 18 V.

Of course, the know it all, will say you can look up the first three items in the data sheet. Yes I know that. But have you tried specifying such a component by adding up all the extensions including temperature range, package variant, pin variant, reel size, extra feature codes,... after seeing hundreds of those when specifying alternate parts?

[temperance]

And I completely agree with connectors as a category. Select the most obvious options: 3075 parts left to choose from... and without spending on hour or two investigating data sheets it is nearly impossible to find out what the difference might be between part XYZQ and XYZD. And the difference can be as much as some detail in a drawing.

About the BH1730FVC. I used the LTR-329. Send proto type board and components to EMS. Phone rings: We are setting up the assembly line and from the data sheet, we see that the LTR-329 has a polarity marking but we can't find it. After some back and forth I went to the EMS to see what was going one and made a guess by shining light into the component. Luckily it worked.