Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Podcast Transcript
Unknown Speaker
Hello, and welcome to the macro fab engineering podcast. I'm your host, Parker Dohmen.
Host 3
Unknown Speaker
So this last week, we've been working more on the simple or super simple power supply. Yep. And then basically testing the op amps.
Host 3
Yeah, yeah. So the op amps that we talked about on the previous podcast, we actually made a breakout board for those. And actually it was, I believe it's on page seven of the datasheet. There's, there's an example circuit that has both two op amps in a parallel configuration to increase the the output capacity. Yeah. So we made a small breakout board that was finished a little bit earlier this week. So been spending most of today actually doing testing on that board.
Unknown Speaker
Yeah. And we put out a blog post about the testing and cool thing is that op amp actually came really close or actually matched the simulations you did in multi sim.
Host 3
Yeah, it's kind of a golden situation. Mostly of the time, when it comes to analog design, you do your simulation, and then you breadboard or you do a breakout board or you do whatever, and you find out that nothing matches up. But today, everything just kind of worked exactly like it should, which is it's fantastic. Yeah, we
Unknown Speaker
kind of had to hack the signal input. Because the we actually don't have a frequency signal generator yet. We'll get one working on it. But you know, we have we have interest interesting equipment at macro fab. I'll put put it that way. So we actually input the calibration signal from the scope right into the
Host 3
board. works out good. Okay, I've dealt with a lot of scopes before that have a one volt output for their calibration wave, the scope that we have as a five volt, one kilohertz square wave was just perfect. And I was able to put that through a potential ometer and control its amplitude. And right now I don't need to sweep frequency on it. So one kilohertz wave was perfect for what I
Unknown Speaker
was doing and just making sure that the you know, the the breakout board worked. Yeah. And we had this, you had this crazy, I think was like a 200 watt resistors biggest resistor I've ever seen. So yeah, I
Host 3
from my own personal shop, I have an eight Ohm 200 watt resistor, because I work a lot with with audio amplifiers and guitar amplifiers. And eight ohms is kind of smack dab in the middle of your output impedance on on amplifiers. So when I work on these amps, and I need to turn the volume up, most of the time, I don't have a speaker load actually connected to it. I just plugged this giant resistor into it, and I can work on it without blowing my ears out. And for our power flight. This giant resistor worked well because you could just throw a ton of juice into it and it'll be fine.
Unknown Speaker
Yeah, we were putting in what I think was like 10 Watts through it today.
Host 3
Actually, I think we got up to 27.7 Watts amps or something close to that. Now.
Unknown Speaker
Eris is pretty cool to set up.
Host 3
Yeah, yeah. So the thing that's great is it it works as simply as it sounds, it is literally just an op amp that has a ton of output juice. Yeah, you put positive negative 30 volts on it, put a signal into it. The board that we designed had a gain of 10. So I put a one volt signal into it, and I got 10 volts out. And and it the we initially tested it with with no load other than the just the one megahertz, maybe on Periscope input, right? And I took a screen capture of what that wave looked like. And of course it's perfect. Yeah, no, you don't have any load. And then and then I put that eight ohm load on there. So we're dumping something like almost point or 700 milliamps Yep. through it. And the wave is identical. Yeah, it's really nice. Yeah. From from an op amp. That's just
Unknown Speaker
it's ridiculous. That was the there was no overshoot and no jitter on it. Yeah. And no oscillation to an oscillation which,
Host 3
which Yeah, that's awesome. Yeah, so
Unknown Speaker
that's pretty cool. The only interesting thing is we don't we didn't have any heat sinks on it. So it got hot pretty quickly.
Host 3
Yeah. So So these packages I was looking at the datasheet and they have a 40 degrees C rise per watt in from the junction to ambient for DC. Well, when when there's no heatsink Oh, okay, yeah, when there's no heatsink so we put a lot of these things and yeah, it was short burst like one second on one second off but it but it worked.
Unknown Speaker
Yeah, it worked. So speaking of cooling on it, we're, we're looking actually looking at how we are going to cool this power supply. And we either going to use ginormous heat sinks, air cooled, you know at the forsure or just go with it. Think water cooling it with some CPU water cooling for enthusiast computers.
Host 3
Sounds like it would work just fine. Yeah.
Unknown Speaker
I think it'd be it's a little more complicated on terms of human we have to have a pump that ever radiator fans. We have that fans anyways and then the copper block and tubing and water and but I think we'll be able to keep the the the op amps a lot cooler and a lot more efficient that way. Yeah, yeah.
Host 3
And all said and done you get a lot more cooling in a much smaller area when you do it that way. I don't know if there's an off the shelf heatsink that would work for forced air cooling because it would have to be huge.
Unknown Speaker
Yeah, it would have to be huge. The dissipate 125 watts. Whereas a water block the size of you know, two inch by two inch can dissipate 125 watts with ease.
Host 3
Unknown Speaker
We actually were looking at I can't remember the company. But they had some basically, they were I can't remember what they call them thermal. It was those that it was the waterblock that you were looking at. They actually just has the copper tube with aluminum squished on it. Yeah, I
Host 3
can't remember the name of it.
Unknown Speaker
I can't remember the name of the company got the link somewhere. When we find it, we'll put it in the blog. Blog posts for this.
Host 3
Yeah, they look they look great. It's a block of I guess aluminum with with a couple turns of copper tubing through it. Yeah, it looks like it will do the trick. You can machine right into the aluminum and mount all your stuff directly on there. Well with insulating spacers. But But yeah, no, it looks like it's gonna do the trick just well, and honestly, it's not that expensive.
Unknown Speaker
Now, I think it was about a, I think it was 150 bucks for the one we were looking at. We it was it was two inches tall by 12 inches long. Yeah. And I think half an inch thick. Yeah, because
Host 3
we're talking about having multiple of these op amp chips on there. Yeah. And having multiple channels available. So yeah, as soon as you add a channel, you double your your bam, yeah, on your op amp. So having, you know, say up to eight op amps on there. It'd be awesome if we could cool them all on one block. And it looks like that might be possible with a block that big.
Unknown Speaker
Yeah. And for isolation, we're looking at some aluminum oxide blocks. We've used those before, and they're awesome. Too bad. I can't, I can't I haven't been able to find some beryllium oxide. But that's a little bit harder to find and a little toxic. But it's inside an enclosure and usually not a big deal. Yeah,
Host 3
the thermal resistance of the aluminum oxide is just It's unreal. Yeah. When you when you do your calculations, you almost don't even included in your calculation. It's pretty
Unknown Speaker
close to what anodized? Aluminum Yes, straight up. Yeah. And actually, I was looking at analyze aluminum spacers to. The only problem with those is that you only get 400 volt isolation with and that would be enough. But I'd like to go at least to a couple kilovolt isolation.
Host 3
Well, the good thing is to with the with the ceramic ones if they chip or if something they don't become conductive. Yeah,
Unknown Speaker
they don't. Whereas if the aluminum oxide, not Yeah, aluminum oxide ones, no anti scratch or chip. They become conductive.
Host 3
It's game over after that. So you can be a little bit more aggressive with the ceramic ones.
Unknown Speaker
Yeah. Cool. Yeah. So now we got to power. The super simple power supply. Yeah, you have to get power to the op amp.
Host 3
That's yeah, that's it. So so the the op amp does the magic. It does all the controlling and all of that jazz, but we still have to give it juice. Yeah. So the good thing is I think we can get away with just a pretty stock linear power supply and you're just gonna have to have a monster transformer.
Unknown Speaker
Yeah, so we're gonna use like, was it a one those that did toroidal a donut transformer? Yeah. I think you've got a source for those.
Host 3
Yeah. I found I found a really great tours. The name escapes me at the moment, but they have really cheap, they're manufactured here in the states and their, their specifications are just unreal. They'll also do custom wound which we may end up having to go with, but but they have up from multi 1000 Watt transformers. Yeah. So it's
Unknown Speaker
a good thing. He's got lots of space in this enclosure. Yeah, yeah. And well and
Host 3
on top of that turtles have a lot less leakage magnetic flux. So you get a lot less crosstalk get a lot less noise buildup in the system. It's just it's kind of a win win with those guys. Yeah, we're gonna have to have a monster bank of capacitors though.
Unknown Speaker
Yeah, um, well, we do have like a I think the chassis is like, eight inches tall. by 919 inches 17 inches wide because you're inside the rails, and then nothing. It's 15 inches deep. So we got a lot of space for, for basically the toil and. And all these caps. Yeah. Cool. Yeah. So I guess we'll go into what we've been looking at and saw this week, or what we call it last night was a rapid fire question which didn't turn into rapid fire. We basically spent way longer on it than we usually do. It's more like news. Yeah. The Love. Here's some news. So I saw earlier this week, this really cool micro usb super cap flashlights. Hmm. And the interesting thing about it is as I guess I never really looked into supercast. Before. As a 30. Fair ad, I'm like, fair ad. I knew I knew Supercats were in the Feride range. But this was it looks a lot smaller cap wise,
Host 3
you get an image up here, it looks like it looks like what you would expect to say 100, micro farad. Electrolytic would
Unknown Speaker
look like Yeah, exactly. I mean, that literally, it would be like a couple 100 volts or 100 volts. This is 2.7 volts. Right? And I got the thinking is, you know, 34 ads is a lot of electrons. Yeah, yeah. And I want to how much weight? It would gain in electron charge? Because electrons have mass. Yeah, mass, right. And how much weight would you your device gain?
Host 3
If it was fully charged, fully charged? If you had 30, fair ads worth of electrons? Electrons? Well, guess 30? What? However many columns? That would
Unknown Speaker
be? Yeah. So we actually before the show, we actually ran the numbers, so we wouldn't bore you. And so it came out to be 5.685 times 10 to negative 12 kilograms. So that's not lots
Host 3
that's it feels a little counterintuitive. It feels like you should be able to hold this cap. And as it charges up, you feel like it heavier. But I guess electrons are that small, that small and that? I wouldn't say that weightless, but they're they don't. Yeah, there's something there, but not much.
Unknown Speaker
Yeah. And then we actually said, Well, how much would one kilogram of capacitors? Or how many? How many capacitor? How many passes? Would you need
Host 3
to have one kilogram to actually have something that you can feel in your hand? Yeah. And the total that we calculated out was 176 billion. So it's a cool exercise. But
Unknown Speaker
yeah, you know, what to be interesting is actually figure out, like for the Tesla Motors car, is figuring out how much power that battery is and how much it weighs empty in full. Hmm. Because when you fill up your car, you're filling it up with, you know, 18, roughly 18 gallons of gas, right? And, you know, well, gallon of water is about 10 pounds. I don't know if gasoline is less, it's probably less than, yeah, gasoline floats on water. So it's less dense, right? So say, eight, eight, I don't know. Where so there's, it's not a it's not a insignificant amount of weight when you fill up your car.
Host 3
So you're questioning what's the weight difference between powering your car off of electrons versus gasoline?
Unknown Speaker
Yeah. So if, because technically, if your car is low on gas, it's more efficient. Because it weighs less. Small. It's still like 100 pounds.
Host 3
But you know, you put you have your car's 2000 pounds, and then you put me in there and it's another 2000 pounds. 100 pounds is kind of insignificant.
Unknown Speaker
It's like it's like, um, you know, all the, like, shaving down all the plastic and trying to make cars as light as possible. And then you like, have this big, you know, you go and eat like a pound of brisket and a pound of sausage. And you eat chips and a big coke and it's like, offset all that work those engineers did that make your car lighter.
Host 3
Unknown Speaker
Ah, okay. Then a research group, I think. Don't remember the university. I will just link it into the blog yet. It's right there, Drexel, Drexel University. They came out with this research that showed about carbon films. I guess it's probably kind of close like graph Maybe they don't mention graphene. So it's probably something some different structure. They give microchips the ability to store electrons like a capacitor. And one of the things that they mentioned in their research is this could get rid of bypass or decoupling capacitors in your designs and future chips. Oh, really? Yeah. And so I thought that was really cool, because I've been doing a lot of FPGA hardware, where you basically sprinkled the entire board with bypass gaps.
Host 3
But they will be, they will be much closer, therefore can be smaller. And they're internal.
Unknown Speaker
Yeah, they're built into the chip. So basically, all you do is power your chip. And you don't even have to have that bypass capacitor
Host 3
anymore. Yeah, yeah. I mean, if you flip over an FPGA board, it looks like it has acne with a cat. What's your bypass caps underneath there? That would be cool. Because, man putting putting bypass caps under like a 512 pin FPGAs just a giant
Unknown Speaker
pain? Yeah. I think that would be very interesting. If this this research starts coming out. And it's, I guess, I guess the thing is, it has to be cheaper than Well, it's gonna cost to manufacture more to do it. Yeah. Because technically, they can actually put capacitors into design. Yeah, by layering silicone down and then metal and silicone and metal, they can make it count that way. It's
Host 3
a pain. And it's really tough to get large value large values when you're talking about the small peak affair adds at best.
Unknown Speaker
But if this enables your point one mics to be internal. And it's cost effective for the chip manufacturer, I guess this will start to come out.
Host 3
Maybe they'll make an op amp that has a couple a couple of 100 micro farad on the front end. And you have a one chip power supply that can do a couple 100 Watts just like their SSBs
Unknown Speaker
it's like a you'll see like the to 220 11 package with his big growth. That's the built in capacitor. Yeah. That's pretty cool. Yeah. And then earlier this week, Obama signed a bill combating counterfeit chips, which we talked about, I think on episode one. I think that's when we talked about FTDI gate I died. It's only been like two weeks. I don't remember.
Unknown Speaker
So what do you think about that? I guess. I mean, they already look for counterfeit chips coming in via
Unknown Speaker
through customs. So I have I actually didn't do too much research into this. I just thought oh, okay, that looks cool.
Host 3
I guess there's really only one thing to say about all this. Thanks, Obama.
Unknown Speaker
I guess so. We'll see how they implemented and go from there if it'll actually be successful. Usually the tighter you squeeze pirates and counterfeiters, the the more they squeeze through your hand.
Host 3
Is that a Star Wars quote? That that's one layer. Yeah,
Unknown Speaker
I think there's more more systems slipped
Host 3
through your fingers fingers.
Unknown Speaker
And then I think it was actually today, Microchip released a notice on Monday, Microchip released a cloud based IDE environment for MP lab called MP lab Express. I've actually never really used MP lab too much the IDE, I've used their IP, which is their inter programming interface, whatever it's called, basically talks to the pic kit, and you can just dump straight hex files into your pics.
Host 3
It's a it's a really stripped down programmer. Which, by the way is awesome. Yeah.
Unknown Speaker
If you don't have a stripped down programmer for your, for your,
Unknown Speaker
whatever tool you whatever tool
Unknown Speaker
you're using, make one as they're awesome for production environments.
Host 3
How engineers don't want to click through a whole bunch of stuff. They just want to load it up. They put my hex in my board. Yep. Yeah.
Unknown Speaker
Yeah, it's not a oh yeah, I need to load up this new code. Click go get coffee. Talk around the water cooler. Go to the bathroom. Come back. Oh, now find the IDS uploaded up and running. Right?
Host 3
Yeah, a lot of the IDS they're fantastic because they have all this wonderful features and all the super cool stuff you can do but they just feel super bloated. Yeah, hopefully this this new pic ID will be cool. Especially with the name Xpress. Maybe it will be really stripped
Unknown Speaker
down or fast. Yeah, I mean, it's gonna be fast if it's online.
Host 3
I saw that pic was Doing something. And I bet you it's in conjunction with all this where you can do pin definitions and select all your registers outside of actually writing code. Oh, and it'll generate it all for you. Yeah, it'll just like if you know, you need SPI, and you need a PWM. And you need all this other jazz, you just click the buttons, and it spits it all into your code. And all the registers are already set up, configured and ready to go. It's kind of funny, because it's 2016. And it's like, wow, this feels like it should have been done a long time ago. But it's cool, great. You know, they're buying out atmo and then crashing it all together and making something cool.
Unknown Speaker
Yeah, hopefully would be interesting is if that does actually in the future is if either atmail rolls out their own, you know, AVR Studio Express or is it as microchip roll their stuff into MP lab?
Host 3
I kind of get the feeling that they're going to roll it all in
Unknown Speaker
the one you would think that make the most amount of sense in terms of maintaining the source code for it.
Host 3
Yeah, cuz I don't know how much they're gonna count out to AVR fanboys you know? Yeah. Just give them their own little like,
Unknown Speaker
well, the the worst of Arduino.
Host 3
Yeah, well, is it gonna be picked?
Unknown Speaker
We know now. Well, actually, Microchip had a, a fork. Yeah, of I can't remember what was called but they had a fork of the Arduino environment that was set up for picks. And then I think with the Arduino update, that was a couple years ago that made it easier to add boards and actual custom stuff. Yeah. Microchip just basically released stuff that worked with that, instead of making their own version. Actually, I think on the pinball controllers was actually programmed original pinball controllers, the pin packs. We programmed in that microchip forked Arduino environment. And it was held. Awesome. It worked, though. I mean, you can't fault that.
Host 3
If it works. It works. It's just how much of a pain does it take to get it to work?
Unknown Speaker
Yeah, I kept going like, we can just use MP lab and Yeah. It's like knocking on deaf ears. Well, I think that will do it for this episode of the macro engineering podcast. I'm your host, Parker Dohmen. And I'm Steven Craig. catch you all next time.
Host 3
