Learning electronics: Release the Magic Blue Smoke

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ante: Apr 9, 2005; SUNSHINE AND RAINBOWS

Bone up on your op amps

# ? Nov 22, 2022 09:34

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# ? May 9, 2024 12:26

ryanrs: Jul 12, 2011

I don't know complex analysis. :rip:

# ? Nov 22, 2022 10:17

Rescue Toaster: Mar 13, 2003

90% of actual EE work (according to the hardware guys I work with) is DFM and EMC.

I mean obviously it depends what exactly you do. Some shops are so large everybody just specializes in 1 thing. Like the PCB librarians. I don't know how you pay anyone to do that job.

# ? Nov 22, 2022 21:35

PRADA SLUT: Mar 14, 2006; Inexperienced,
heartless,
but even so

ante posted:

Bone up on your op amps

4-resistor bias
Basic filters
I2C or some other low-speed interface
Buck converters
Bypass caps

And usually some dead simple ohms law question that fucks up 90% of seniors

# ? Nov 22, 2022 23:01

Splode: Jun 18, 2013; put some clothes on you little freak

Rescue Toaster posted:

90% of actual EE work (according to the hardware guys I work with) is DFM and EMC.

I mean obviously it depends what exactly you do. Some shops are so large everybody just specializes in 1 thing. Like the PCB librarians. I don't know how you pay anyone to do that job.

And of course they don't ask you much about this in the job interviews. They should ask about software tools and DFM, but instead they ask you trivia about op amps and the intracies of various DC/DC power supplies that only comes up a few times a year.

There are often a lot of questions about EMC theory, but just the abstract theory. I've never been asked to calculate anything EMC related.

YMMV but this has been my experience.

# ? Nov 23, 2022 02:25

Stack Machine: Mar 6, 2016; I can see through time!; Fun Shoe

I've seen a lot of seniors and new grads stumble on "here's a series RC circuit. How does it respond when we take this node from 0 to 1V". and a lot more lock up when the R is swapped for an L. I think these kinds of "Here's a circuit. What does it do?" questions are pretty standard in interviews and the kind of circuit depends quite a bit on the job description and the interviewer's preferences.

Don't be surprised if you're asked some kind of programming question too, especially if you'll be touching microcontrollers or doing something else digital. I like to ask something relevant to the job and the rest of the interview questions (e.g. bit bang a SPI interface in the language of your choice, make up a reasonable API for the GPIOs) but I was asked a lot of algorithms type questions when I was job hunting.

I've never been part of an interview where anybody was asked any questions specific to the use of a piece of software, so if that's what you mean by tools, don't worry too much. Every shop has their own way of doing things and for EE jobs usually figuring out how to do the thing with the tool is much quicker than solving the actual technical problem.

I have heard of "lab interviews" though, so knowing your way around a multimeter, an oscilloscope, a function generator, etc, would be useful for that. I think those were mostly for product evaluation engineers, so people whose job is about half making measurements in the lab.

# ? Nov 23, 2022 02:27

Rescue Toaster: Mar 13, 2003

What's funny is I did a 2 year electronics and then went on to computer science, and I think I could smash most EE interviews if they're focused on anything short of high level RF or control systems theory. And I have no problem setting up equipment in the lab. But I wouldn't get an interview anywhere because I don't have an actual 4 year EE and have only been doing software professionally and electronics for my own amusement.

# ? Nov 23, 2022 03:26

ante: Apr 9, 2005; SUNSHINE AND RAINBOWS

The first time I had an interview where they asked me to design a buck regulator I was like lol are you serious, just sort by price on Digikey and follow the reference

Alternate answer TI WebBench

# ? Nov 23, 2022 05:06

ryanrs: Jul 12, 2011

Maybe I should also mention I am 42, have no degree, and I'm entirely self-taught. I do have a number of multimeters, though, including an HP 3457a. So I am down with multimeter chat. I am also down with writing low-level mcu peripheral code, and I'm learning FreeRTOS for my current project.

Here's my latest project over in AI. Sort of an IoT dev board that crams together a bunch of stuff I've been wanting to play with. Right now, I'm focused on gaining experience with PCB assembly houses, because I want to use QFNs and and other stuff that's hard to solder by hand. For example, the microcontroller board linked above is build from an Adafruit dev board, but on the next rev I want to use this raytac module directly. It has a sparse BGA footprint underneath and probably should be x-rayed or something after soldering.

I think I've made 20-30 boards? Almost all worked with zero or minimal rework.

I'm sure I have weird gaps in my knowledge, but I'm also able to design circuits and get boards manufactured from start to finish, which should be pretty useful I hope.

# ? Nov 23, 2022 05:10

Foxfire_: Nov 8, 2010

When I interview people, I usually ask them to talk about any cool thing they've done in the past and what was hard about it. You can usually tell pretty quickly whether someone knows what they're talking about or if they worked near something but didn't really contribute to it. Even a new grad or former self taught hobbyist should be able to come up with a "here's a neat thing I did, this part of the design was tricky, I solved it this way" kind of general story

# ? Nov 23, 2022 05:50

Splode: Jun 18, 2013; put some clothes on you little freak

ante posted:

The first time I had an interview where they asked me to design a buck regulator I was like lol are you serious, just sort by price on Digikey and follow the reference

Alternate answer TI WebBench

Yeah exactly.

I don't actually give a single flying gently caress what the boost capacitor does or why it's the value it is, I just do what the chip designer tells me to do and focus on the rest of the circuit.

ryanrs posted:

Maybe I should also mention I am 42, have no degree, and I'm entirely self-taught. I do have a number of multimeters, though, including an HP 3457a. So I am down with multimeter chat. I am also down with writing low-level mcu peripheral code, and I'm learning FreeRTOS for my current project.

If you're actually building stuff and it works you'll be fine.

Splode fucked around with this message at 07:24 on Nov 24, 2022

# ? Nov 23, 2022 11:33

Dominoes: Sep 20, 2007

ryanrs posted:

What's a good non-China PCB fab + assembly factory for small hobbyist projects, like PCBWAY? I need some regional diversity in suppliers. Fancy US assembly places are likely too expensive for me. I'm looking for pretty basic single- and double-sided SMT assembly on runs of 2-10 boards. 0402 and QFN and other stuff I don't want to hand solder.

(not racist, but kinda lunar new year-ist)

Good thought, but there is none. Digikey recently announced a service that might change this, however.

# ? Nov 23, 2022 22:22

PRADA SLUT: Mar 14, 2006; Inexperienced,
heartless,
but even so

ryanrs posted:

Maybe I should also mention I am 42, have no degree, and I'm entirely self-taught. I do have a number of multimeters, though, including an HP 3457a. So I am down with multimeter chat. I am also down with writing low-level mcu peripheral code, and I'm learning FreeRTOS for my current project.

Here's my latest project over in AI. Sort of an IoT dev board that crams together a bunch of stuff I've been wanting to play with. Right now, I'm focused on gaining experience with PCB assembly houses, because I want to use QFNs and and other stuff that's hard to solder by hand. For example, the microcontroller board linked above is build from an Adafruit dev board, but on the next rev I want to use this raytac module directly. It has a sparse BGA footprint underneath and probably should be x-rayed or something after soldering.

I think I've made 20-30 boards? Almost all worked with zero or minimal rework.

I'm sure I have weird gaps in my knowledge, but I'm also able to design circuits and get boards manufactured from start to finish, which should be pretty useful I hope.

There's nothing wrong with that experience, but I would put it in the "entry-level PCB designer" minimum and it gets significantly more complex when you start to move into higher speeds and larger stackups. High-speed transmission lines, high-current boards, controlled impedances, RF, etc, are far more complex and sensitive to design and layout issues than "microcontroller does a thing"-style boards.

If I was interviewing you for a design position and you gave me that portfolio, I would ask how you chose your stackup (looking for rationale for thicknesses and layers, prepreg, and dielectric), and what your validation plan for the finished boards, and I'd also ask you about some basic routing. I'd guess for those boards you probably just went with whatever PCBWay's default options were, so I'd be looking to know if you understood when and why you would deviate from "4-layer 1.6mm thickness 1/2oz copper weight FR4" sort of options.

Splode posted:

I don't actually give a single flying gently caress what the boost capacitor does or why it's the value it is, I just do what the chip designer tells me to do and focus on the rest of the circuit.

Yeah, this is precisely why I ask questions like this. If an engineer can't tell me what a cap does or where it goes in a basic circuit like a buck converter, there's a fundamental issue with their engineering knowledge. Too many interviewees try to hoist a data sheet example like it's a shield against understanding basic circuits, or pull a "lol nobody designs that way ~in industry~, let's move on please".

Also, design issues can get caught in reviews from people other than the designer, so it's extraordinarily useful to have everyone on your team with a passing understanding Sophomore-level EE, even when just copying reference designs.

# ? Nov 23, 2022 23:21

Shame Boy: Mar 2, 2010

PRADA SLUT posted:

If I was interviewing you for a design position and you gave me that portfolio, I would ask how you chose your stackup (looking for rationale for thicknesses and layers, prepreg, and dielectric), and what your validation plan for the finished boards, and I'd also ask you about some basic routing.

Cuz I saw a youtube video in this thread that said to use these settings so I don't have to think about it too hard

# ? Nov 23, 2022 23:23

Shame Boy: Mar 2, 2010

Honestly though the time I actually had to Think About impedance control for a four-layer board it was basically a combination of "what's the stackup that I have to think the least about / has the most examples available / is mentioned in the datasheets of the chips I'm looking at" and "which is the material JLPCB has that does what I need while still being cheap", is that good enough :shrug:

# ? Nov 23, 2022 23:26

ante: Apr 9, 2005; SUNSHINE AND RAINBOWS

There's a world of difference between "design this circuit that you looked at in class ten years ago and literally everyone would call you a moron for building on the bench" vs "analyse this circuit that is a buck converter but I'm not going to tell you that"

The former is a bad judge of EE competency imo

# ? Nov 24, 2022 00:07

PRADA SLUT: Mar 14, 2006; Inexperienced,
heartless,
but even so

I would argue "use a cap and an inductor to turn a square wave into a line" isn't really some abstract "remember this exotic circuit from 10 years ago", so much as it is a "do you know how a R/L components work enough to design a three-component analog circuit". Seems like that should be something you can do at any point in a career, especially if you're looking for a new job.

# ? Nov 24, 2022 01:05

Splode: Jun 18, 2013; put some clothes on you little freak

PRADA SLUT posted:

Shame Boy posted:

Oh you think you're good at electronics huh? Name 10 resistors.

# ? Nov 24, 2022 07:14

Marsupial Ape: Dec 15, 2020; the mod team violated the sancity of my avatar

I�ve been meaning to admit to this particular blunder�or rather unwanted bounty.

Back in July, I was up ordering some bullshit I didn�t need off Parts-Express when I should have been asleep. During check-out a little pop up told me that I was eligible for a special deal: 14 little OEM flat panel speakers for just $10. Hell yeah, make a couple BT speakers out of those.

Anyway. A week later I gotta box of 144 of these goddam speakers. Not 14. Still just 10 bucks, though.

Anyway, somebody got a tutorial for wiring line arrays?

I�m half-rear end thinking about keeping the top layer and donate the rest to a high school or something.

# ? Nov 24, 2022 09:19

Dominoes: Sep 20, 2007

ryanrs posted:

next rev I want to use this raytac module directly. It has a sparse BGA footprint underneath and probably should be x-rayed or something after soldering.

I wish Nordic would make their own certified modules like ST does.

That said, I've used the one you linked (or maybe a similar one) and it's fine.

I have a footprint floating around for that; LMK if you need it. The soldering is kind of weird, in that you're soldering one PCB to another, and yea, the pads are un-visually-inspectable. (But relatively large) It's not BGA in the usual sense, in that there are no solder balls.

# ? Nov 24, 2022 14:25

mobby_6kl: Aug 9, 2009; by Fluffdaddy

BattleMaster posted:

It does show how to read at least. My interpretation of the stuff shown here for reading a register:

Send start condition
Send device address
Send write bit
[Device sends ACK]
Send least-significant register address byte
[Device sends ACK]
Send most-significant register address byte
[Device sends ACK]
Send restart condition
Send device address
Send read bit
[Device sends ACK]
[Device sends least-significant register content byte]
Send ACK
...
[Device sends most-significant register content byte]
Send NACK
Send stop condition

You didn't post anything that says how to write to an address though. My instinct based on other I2C devices is that it's essentially the same but you send a write bit after the restart condition and then write bytes instead of read. But don't rely on that just in case.

Thanks for looking into this! After more research it turned out to be more more of an API problem than I2C. Despite what it looks like, the HID I2C doesn't seem to just let you talk to the device directly (probably for a good reason).

I ended up doing some reverse engineering on the update binary I had available and I could see essentially what I think are the I2C reads/writes wrapped into the Output/Input report interface. You can see in the buffer it specifies the 0x8050 address as well as the #bytes to read (04).

It then responds with a 5-byte header and data in the buffer. Other than some boilerplate initialization and error handling, this was the entire solution lol.

C++ code:

	memset(buf, 0, sizeof(buf));

		// From sniffed call:
		//0e 20 00 00 05 01 80 50 00 04
		buf[0] = 0x0E; // Report id (14)
		buf[1] = 0x20; 
		buf[2] = 0x00;
		buf[3] = 0x00;
		buf[4] = 0x05;
		buf[5] = 0x01;
		buf[6] = 0x80; //address
		buf[7] = 0x50; //address
		buf[8] = 0x00;
		buf[9] = 0xFF; // 04 bytes to read? let's try more

		rid_write(handle, buf, 65);
	
		//read back configuration
		do {
			hid_get_input_report(handle, buf, 65);
			//print the data
		} while (buf[4] == 0x3c) // data in buffer, 3c is max

So the app is done and I posted it on several forums, now I just need someone ~~dumb~~ brave enough to run an executable made by a stranger on the internet :v:

# ? Nov 25, 2022 10:01

I would blow Dane Cook: Dec 26, 2008; Can't post for 29 hours!

https://www.youtube.com/watch?v=JTx_DlWeRhE&t=1209s

# ? Nov 25, 2022 10:42

Fanged Lawn Wormy: Jan 4, 2008; SQUEAK! SQUEAK! SQUEAK!

I have a power question.

There's a project I started when I was working half-time back in 2020, and I wanna try and finish it after years on the back burner.
I saw pictures of a UFO lamp online once, and decided I wanted to build my own. I designed it in Inventor and I've done some print tests of the body to make sure I liked it and things were aligning.

But I'm not sure I like how I've done the power for this, and wanted to see if anybody had suggestions. I really don't wanna use a power cord on this, cuz it's just cooler not to have a cord.

My design is a bit fancier than some of the others out there. I am using Neopixels around the outside perimeter to give it optional effects on the outside edge. In the picture below, that's waht the black/yellow bit you see is, it's the location of the tape and a representation of the light beam. Then, I'm using and RBGW neopixel ring for the downlight - I don't plan on using the light output of this for much more than a reading light, or in fairly dark conditions anyways. The design at the moment uses AA batteries arranged in a hexagon around the body. The top lifts off, and so this picture is just the bottom of the shell.

Right now, the design uses 32 neopixels on the exterior, and 16 on the downlight. That's 48 pixels total, with a maximum power draw of 1.4A at 5V. Now, in practice, it'll be much lower than that. If I had to guess, with just using white on the bottom is going to me ~.5A, probably less. (I'm using the 60mA per pixel math, knowing full well that that is at full RGB, and I won't be doing that, plus I've heard the chips these days pull less power.

I think my original plan for power was 2 sets of 3 batteries in parallel - so ~4.5V and 4000mAh, meaning maybe 4-ish hours of power?

Would re-designing for Li-Ion or LiPo Batteries be worth the effort? It seems to me like I could put a USB charger on this and make my life easier long term.

# ? Nov 26, 2022 05:13

Wandering Orange: Sep 8, 2012

It seems like a no-brainer to redesign if you can stomach the increased costs & complexity for the batteries and a charger as just a pair of 18650 cells could get you 3.7V and 5Ah, or better. I don't think I'd want to deal with replacing 6x AA batteries often but I hate non-rechargeable anything in this day and age so my bias is showing.

# ? Nov 26, 2022 05:36

Sagebrush: Feb 26, 2012

NiMH AAs are really good and pretty cheap these days. I have a huge pile of Eneloops and am no longer bothered by designing my devices to use AAs. I will use 18650s for high performance devices, of course, but rechargeable AA convenience is really hard to beat.

The decision basically comes down to whether you want simple wiring and the ability to buy new batteries anywhere on earth in an emergency, but use a special charger -- or slightly more complicated wiring, special batteries, but can charge through USB or whatever. No waste either way.

.... I just realized there's probably an IC out there that would let me USB-charge NiMH batteries right in the device. Holy hot drat. Best of all worlds! I gotta look into this

# ? Nov 26, 2022 06:12

Fanged Lawn Wormy: Jan 4, 2008; SQUEAK! SQUEAK! SQUEAK!

Wandering Orange posted:

It seems like a no-brainer to redesign if you can stomach the increased costs & complexity for the batteries and a charger as just a pair of 18650 cells could get you 3.7V and 5Ah, or better. I don't think I'd want to deal with replacing 6x AA batteries often but I hate non-rechargeable anything in this day and age so my bias is showing.

Y'know, I hadn't though of 18650s. That seems like it'd be easy enough. Adafruit's got a nice lil charger interface too, so it wouldn't be a hard integration.

Sagebrush posted:

The decision basically comes down to whether you want simple wiring and the ability to buy new batteries anywhere on earth in an emergency, but use a special charger -- or slightly more complicated wiring, special batteries, but can charge through USB or whatever. No waste either way.

.... I just realized there's probably an IC out there that would let me USB-charge NiMH batteries right in the device. Holy hot drat. Best of all worlds! I gotta look into this

Slightly more complicated than necessary is the name of any project I take on lol

# ? Nov 26, 2022 17:07

Sagebrush: Feb 26, 2012

I really love screwing around with batteries and power systems. I have gradually gone through my house and all my electronics and have gotten it to the point where everything rechargeable I own, pretty much, runs on one of four power sources:

- NiMH AAs
- 18650s
- Makita batteries (18650s in disguise, natch)
- USB-C (and/or wireless charge pad).

My laptop, keyboard, camera, phone, power bank, etc all use USB-C. My flashlights, mouse, video game controllers, airplane headsets, stuff like that run on AAs. High power things like my custom bicycle lighting system use 18650s. And all my power tools use Makita batteries, either natively or through some 3D printed adapters I made (e.g for my TS100 soldering iron, my work lights, etc).

It's nice to not have to constantly be digging around for the right cable or battery or charger.

# ? Nov 26, 2022 22:49

Shame Boy: Mar 2, 2010

Holy crap Carlson's latest video:

https://www.youtube.com/watch?v=Shg7VNoIL_g

"This is my Tek scope collection. That's actually just a portion of it, it actually goes all the way around."

"I've added to this collection since then."

# ? Nov 27, 2022 00:51

ante: Apr 9, 2005; SUNSHINE AND RAINBOWS

Wonder how many would have to go missing before he even noticed

# ? Nov 27, 2022 01:47

Shame Boy: Mar 2, 2010

ante posted:

Wonder how many would have to go missing before he even noticed

He strikes me as the kind of guy who would immediately notice if you moved one so much as an inch out of place

# ? Nov 27, 2022 01:59

VictualSquid: Feb 29, 2012; Gently enveloping the target with indiscriminate love.

That is a stupidly large scope collection.
I say that as someone who used to work in a scope factory.

# ? Nov 27, 2022 02:03

Rescue Toaster: Mar 13, 2003

My collection is small but I have one of those analog 1Ghz tek scopes with the microchannel screen, the 7104. https://w140.com/tekwiki/index.php/7104

It still works great and doesn't have burn in but I never use it. I wish there was someone I could donate it too but I can't imagine trying to ship it.

# ? Nov 27, 2022 16:10

Charles Ford: Nov 27, 2004; The Earth is a farm. We are someone else’s Ford Focus.

I've just got:
- Gould OS3000, an old analog scope (only does 40MHz)
- HP 16500C, an old logic analyser (CRT touchscreen with 192 digital inputs and two oscilloscope inputs as well as a timing card - worth 5 digits when it was new in like 1990, it's still very good if you need to capture an entire 16 bit databus, address bus and control signals. Can do "reverse assembly" (by which they mean disassembly) where you feed it datafiles you make with a DOS app still on the Agilent site, and has support for I think ELF symbol files, though I haven't used any of that, just a punch of signals for computer expansion ports and such and looking at the signals raw. The oscillloscope screen is laughably low refresh rate, but I'm not sad I have it or anything. I would like to get the ethernet card for this so I can use it as an X server and control it remotely)
- HP/Agilent 54622D digital oscilloscope (100MHz, but it's neat, as well as two analog inputs it has 16 digital inputs, and is way more responsive to signals than the logic analyser. Also has an asteroids game easter egg).

The one Tektronix thing I really want though isn't test equipment, it's a '70s computer, a 4050-series. Made famous in things like Battlestar Galactica with the storage CRT, the model with built in BASIC and a tape drive. They appear sometimes on eBay for thousands but I'm hoping I can get a more reasonable one if I just wait for a local surplus or something, though not really hopeful. I wouldn't mind a broken one (assuming the CRT is fine) to just fix.

# ? Nov 28, 2022 01:25

Shame Boy: Mar 2, 2010

I only have an old beat up analog scope and a DS1054z cuz I live in a small apartment, but my parents are finally gettin' ready to move out of their old house now that my dad (who's an EE) is retiring and dad is going through his shop to thin it out a bit (it's a pretty big building and has over three decades of accumulated dad stuff in it, not even counting the stuff he brought with him when he first moved there). He's always been a bit of a hoarder so there's all sorts of fun stuff buried in there, and I get first dibs on all the weird old electronics stuff before he puts it up online or whatever so I might be posting some of that in the thread in the coming months if anyone wants it.

The one thing I've claimed so far is his signal generator, which I forgot the make and model of but it's a nice one with a huge milled aluminum knob on the front (seriously this knob is like 8 inches in diameter) and I'm totally keeping that for myself. He also showed me his collection of TI part catalogues from the 80's and 90's but apparently some TI fanboy group online wanted those real bad so they can have them. Oh and he's got a big box of old phone wires which I have no use for that he was trying to get me to take, but the box itself was an authentic 1980's era Government Cheese box that once contained genuine American Government Cheese and honestly I want that more than the wires :v:

# ? Nov 28, 2022 01:47

Charles Ford: Nov 27, 2004; The Earth is a farm. We are someone else’s Ford Focus.

Shame Boy posted:

He also showed me his collection of TI part catalogues from the 80's and 90's but apparently some TI fanboy group online wanted those real bad so they can have them.

I have "The TTL Data Book for Design Engineers" that my dad gave me when I was little, it's like 1.5" thick yellow-covered collection of a bunch of things including datasheets for every TTL logic IC they sold at the time. It was very handy in my youth trying to understand digital electronics and use chips I'd recovered from old equipment (or my dad's collection of previously recovered chips) but it was also just kind of fun to look at and spark the imagination. As well as pinouts and descriptions, it had equivalent circuits and explanations for why things were the way they were, quite educational!

# ? Nov 28, 2022 02:13

ryanrs: Jul 12, 2011

One time I made a buck converter that hummed, even though the switching frequency was >100 kHz, and even under load (so not related to burst mode stuff). The circuit did work, but I didn't think it should be making any noise at all.

The culprit was the output capacitor. I used a very low ESR polymer cap, which caused subharmonic oscillations in the regulator. Something about the low ESR not playing nice with the regulator's internal compensation? The solution was to use a cheaper, higher ESR electrolytic capacitor on the output. Didn't need to re-spin the board because the footprints were the same.

# ? Nov 28, 2022 06:52

Splode: Jun 18, 2013; put some clothes on you little freak

ryanrs posted:

One time I made a buck converter that hummed, even though the switching frequency was >100 kHz, and even under load (so not related to burst mode stuff). The circuit did work, but I didn't think it should be making any noise at all.

The culprit was the output capacitor. I used a very low ESR polymer cap, which caused subharmonic oscillations in the regulator. Something about the low ESR not playing nice with the regulator's internal compensation? The solution was to use a cheaper, higher ESR electrolytic capacitor on the output. Didn't need to re-spin the board because the footprints were the same.

I heard a similar story from an old boss.
They had developed a pay phone system for prisons. They received a few complaints that prisoners were getting charged too much.
It took forever for them to work out the problem, until they actually saw a prisoner using the phone: he was pretty agitated, and tapping pretty hard on the phone as he talked.
This was flexing a capacitor on the board, which was in turn generating a voltage via the piezo electric effect, that was close enough to the "minute has passed, increase the bill" signal the system used. THAT was why the prisoners were getting unfairly billed.

It's a second-hand story, so I have no idea how long it took them to actually diagnose that, but I bet it was either instantly from a bolt of pure inspiration, or it took absolutely forever.

Charles Ford posted:

I have "The TTL Data Book for Design Engineers" that my dad gave me when I was little, it's like 1.5" thick yellow-covered collection of a bunch of things including datasheets for every TTL logic IC they sold at the time. It was very handy in my youth trying to understand digital electronics and use chips I'd recovered from old equipment (or my dad's collection of previously recovered chips) but it was also just kind of fun to look at and spark the imagination. As well as pinouts and descriptions, it had equivalent circuits and explanations for why things were the way they were, quite educational!

These funny old chips still show up from time to time, pretty handy to know

# ? Nov 28, 2022 08:24

ante: Apr 9, 2005; SUNSHINE AND RAINBOWS

My nice expensive low ESR tantalum caps kept blowing my fuses just due to inrush.

# ? Nov 28, 2022 08:34

ryanrs: Jul 12, 2011

My tantalum caps kept blowing just due to inrush.

# ? Nov 28, 2022 08:49

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# ? May 9, 2024 12:26

Splode: Jun 18, 2013; put some clothes on you little freak

Is it true that tantalum capacitors catch fire if they're exposed to too much voltage?

# ? Nov 28, 2022 10:42

The Something Awful Forums > Discussion > Hobbies, Crafts, & Houses > Learning electronics: Release the Magic Blue Smoke

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