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[kastein86]

Well some jerk is cratering Twitter right now, which I also barely use, so I might be barely using this again in the near future.

[kastein86]

Time to digital converter chip - seems good for speedometers, tachometers, fuel/fluid/gas flow meters. SPI interface, picosecond resolution.

I foresee using this a lot in tachometer/speedometer type circuitry.

[kastein86]

Tiny, low power, up to 26V common mode, 1% gain error, preset gain!

I use these or the older INA199 series almost everywhere.  They’re pin compatible (at least the SC70 package is), so if you have an older INA199 design you can drop the same gain INA21x series in with no real PCB artwork changes.  These things rock, they take all the annoyance out of building a current shunt measurement circuit.  Pick an amplification factor and shunt resistor, drop one of these and a decoupling capacitor on the board, feed it into your ADC and you’re done.  Bandwidth is nothing to write home about, but that’s usually not very important when measuring high currents.

[kastein86]

Probably originally intended as a main relay for automotive applications.

I don’t even know what I’m going to use this for but I want one.  This was found when I clicked the sort-descending button on the current rating column in Digikey’s search results for latching relays and was absolutely sure there was a typo involved until I checked the datasheet.

It’s latching, handles 260 amps, waterproof, and they tell you what connector mates with the winding terminals right in the datasheet (AMP 184046-1, by the way.)  What’s not to love?  Oh, the price.  It’s not cheap.

Actually, here’s a whole catalog section full of badass power relays.  http://www.billavista.com/atv/pdf_index/files/electrical/Tyco%20Electronics%20-%20High%20Current%20Devices%20-%20Switches%20and%20Relays.pdf

They even give the socket and terminal part numbers required to actually use these.

[kastein86]

This aint your grandfather's 3-axis accelerometer.

The price is a shocker compared to most things I’ll be featuring, but sometimes you gotta do what you gotta do.  Available in +/- 25G through 500G scales, for when you really need to measure some brutal acceleration.

Temp sensitivity is a bit of a bummer (-20% response at -40C, +30% response at 125C?  Really?) but I was able to compensate for this using a cleverly designed amplifier with a platinum RTD (bonded to the accelerometer cover) as part of the feedback divider, bringing the temp response down under 1% across the entire specified operating range.

[kastein86]

Throw your thermistors away!

Much more expensive than a regular old exponential curve thermistor, but the response is incredibly linear.  I found this (and used it) while designing an entirely analog accelerometer output temperature compensation circuit.  Got nonlinearity over the -40 to +125C range from -20%/+30% to down under 1% across the entire range with only a handful of components!

They make a few versions of this unit, with the only difference being the tolerance.  Lower tolerance = higher dollars, pick your poison.  PPG102A1 is 0.06% and $5.61/qty1, B1 is 0.12% and $4.66/qty1, C1 is 0.24% and $4.18/qty1.  I decided the 75% reduction in nonlinearity was worth the extra $1.43 and went with the PPG102A1.

The accelerometer being temp compensated will be featured later.

[kastein86]

128A current capacity, high side smart switch, TO218

This thing is straight up awesome.  I’d say all the neat features but really every feature it has is neat so just read the datasheet yourself.  128 amps worth of high side driver in a package that small is mind boggling, I’m not used to Rds(on) values this low yet.

[kastein86]

Roll-your-own current sense element and housing, waterproof!

This is really cool if you need to measure current, say, in an engine compartment, and need to do some sort of processing (example: spectral analysis, true RMS, averaging, data bus packetizing, etc) or preamplification before the signal goes out onto your wiring harness.  Includes a cavity sized for a 35x40mm PCB, two large terminal lugs for the current sense element, and a four pin Molex MX150 connector for harness interfacing.  Max power dissipation is 36 watts and resistance is 100μΩ, thus maximum current 600A.  Roll your own board, solder it in, epoxy pot it and off you go.  They’re available on Mouser and from other distributors for approximately $12, quantity 1.

[kastein86]

Awesome Electronic Components

I decided to put this series of posts together because a couple fellow embedded systems / electrical and computer engineering sorts I corroborate with on a daily basis suggested I should, since I’m constantly finding really neat components that we all like, but don’t have a use for yet.  This should keep all those “cool toy” type components linked in one easy to find location instead of having to search IRC logs for the datasheet links.

PS: I do not work for ANY of the companies whose products I will be featuring here.  Mostly I find them via digikey/mouser/allied/octopart (et al) while looking for something else entirely, but think they’re too neat to simply forget about.  If you are a marketing person at an electronic component manufacturer reading this, by all means send me links to neat new products you come out with, but I may or may not feature them based on whether I think they’re really cool for some arbitrary reason or not.