The Amp Hour

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An Interview with Tom Lee Sep 23, 2019

Show notes

Welcome Dr Thomas (Tom) Lee of the Microwave Integrated Circuits Lab (SMIrC) at Stanford University!

This episode is sponsored by Rohde and Schwarz. Check out AskAnEngineer.us for more info about their value line test equipment.

Tom is friends with two past guests, Jeri Ellsworth and Kent Lundberg
Tom owns a LOT of scopes (200 or so)
First scope was a Heathkit
The Tek 485 had nice user design
"I didn't like an intermediate layer."
John Addis and Wink Gross designed the important parts of the 485
The 485 added a superfast square wave to the front panel important for calibrating a 350 MHz scope
Protection circuits
Tom got started in electronics fixing TVs
He then went to work for the founders of Wavetek (but not directly for the company) with people like Joe Deavenport
Tom went to MIT and worked under Jim Roberge (check out the video series where Jim is lecturing on-camera)
He proposed a thesis that was the world's first integrated CMOS radio
Marvin Minsky
"The thesis doesn't change the world...it changes you"
CMOS was considered crap, was mostly used for wristwatches and calculators
Other types of MOS and BJT circuits were considered to be much better.
Tom used MOSIS, the IC bundling service mentioned on this program before.
Didn't have PDKs
Magic from Berkeley allowed Tom to see the DRC errors as they happened.
He ended up building an FM radio...without any inductors!
Made gyrators into inductors
Moved to Analog Devices where he learned a lot from Barrie Gilbert and Paul Brokaw
Moving back to California and went to work for a startup RAMBUS
Stanford wanted someone to do RF and give a first class on RF chip design
Tom started in 1994 and started the first microwave IC lab.
Tom and his grad students created the first GPS CMOS receiver
Used to be 1 GHz and above is microwave
Many of Tom's students are (truly) seeing Maxwell's equations for real for the first time
What are the mental models?
Tom said he "inflicts history on students". This is also in the early chapters of Tom's book, Planar Microwave Engineering
Maxwell didn't use vector calculus, he used quaternian form.
Every course Tom teaches has a lab, including his undergrad lab which involves copper tape and making a radio.
A lot of faculty have never built stuff
He is now working with students on mmwave and 5G (because that's where a lot of the research dollars are right now)
Beamforming to get aggregate bandwidth
Printed electronics for power delivery, serving devices that are in the mW level not the W level
Feature sizes of CMOS
Tom is on the board of Xilinx
Tom is taking a year sabbatical and working on a book about instrumentation
He hopes to ask many of the creators about the secrets inside the test equipment he often is reverse engineering
Jim Williams told him to buy a rubidium clock (standard) at a flea market.
Worked at DARPA, where his office funded development of a chip scale atomic clock
That chip subsequently released a bit of smoke in the space station...
Read more about Tom's research on his group's website

An Interview with Ken Burns Sep 16, 2019

Show notes

Welcome Ken Burns of TinyCircuits!

TinyCircuits is located in North East Ohio (NEO), in Akron.
Ken also attended the University of Akron
Decided to stay in the Midwest
Past guest Todd Bailey talked about going to a job for working with graybeards
Ken used to work for Avid, which was later bought by Avnet/E14.
Since it's a design shop, he got to try out different types of electronics.
This included learning the entire process and taking it to a CM.
Wireless HART developed by Rosemount (now Emerson), based on 802.15.4
MACtek made a PC based interface device for wireless HART
Dust networks bought by LT
The standard uses a negotiated time for when to wake up to save power.
Pepperl and Fuchs bought out Mactek
Decided to leave Avid to start a company
Wanted to make a smart sensor platform
This was late 2000s (2008), so Arduino was getting started
TinyDuino (and the other boards with the same form factor) is 20x20 mm
TinyCircuits have launched 3 kickstarters
Digispark was 2 months prior
This was early kickstarter days. His Kickstarter video recorded rough.
The stretch goal was to do mfg, inspired by companies like Dimension Engineering
Couldn't have done it otherwise because of the volumes being low per board
Kickstarter money worked as seed money
Design was done, but the manufacturing all the problem
Example system is a processor board + USB shield + GPS (for tracking cats)
Was in MAKE magazine for that kit
Everything is open source
Didn't need as many feeders as they got for the PNP machine.
Bought a used machine
Machine was from 1996
It had 80 feeders included and was bought with the reflow oven
All delivered for 25K
Juki
Started with 0402
Bought it from a company that was reputable
A month of tinkering to get it started
The bigger learning curve is making consistent product
"Paste is by far the most critical step in the process"
Yields started at 40%
Need to use fresh paste every time
Yield is 99% now
Dek 265 helped make things more consistent. Got it a year after original stuff for $3K
They are now running with a Panasonic SP60
Got a new PNP 2 years ago, also from Juki.
New machines allows small runs or big runs
Allows testing of a lot of different products
It's gotten much cheaper to send it out than when they started.
Doing manufacturing allows you to do a higher mix, which might be cost prohibitive with sending out to a CM.
TinyCircuits has done some CM work where it makes sense. Ken says they're not going to offer ISO9001 or anything.
It makes sense if the customer wants something custom designed
Robotic golf caddy
Chris asked what customers are asking for at TInyCircuits.
Roadmap is higher end stuff
Whiskers are breakout sensors.
They are now funding on Kickstarter!
5 pin input mux allows you to talk to different versions of the same sensor (up to 16)
Dealing with the Tariff
Selling batteries on digikey
"18650 is the biggest thing we sell on eBay"
Selling on digikey and mouser
Johnny 5 / firmata (used by past guest Jason Huggins)
Latest stuff supports circuit python
Little Bits sold to Sphero for unknown amount after raising $70M.
Working with group out of MIT
tinycircuits.com
They work out of the old Goodrich plant in Akron

Dotty Ernest Annty Frost Sep 09, 2019

Show notes

Chris spent too much of his camp working on giving a talk
Dave winged it when he spoke at a Renesas 2010 event
Dave recorded at the hotel room afterwards
At Disneyland Star Wars you can build your own droid
James Meigs of Popular Mechanics
RF slides
The talk Chris gave at CCCamp is now posted as well
Hank Zumbalen on The Amp Hour
App note "Staying Well Grounded"
Book on RF layout
Scotty from Strangeparts JLC video
Does anyone know of a standalone loss leader factory?
Dave building the programmer for the 3 cent micro
$10B lost to trade war so far for Electronics Manufacturers
Tariff
During the show we found it acts like VAT or GST, it's added to the end product/delivery area
- ie. Dave does not get charged Tariff even though he gets parts coming from China via the US
Chris has started seeking out tutoring
Mentorship
Dave learning French and German
The term "Professional Engineer" will be a protected term in Victoria (Australia)
Wi-Fi was invented at CSIRO
How to to pronounce various hexadecimal numbers, incluing 0xDEAF ("dotty ernest annty frost")

Thanks to fdecomite for the picture of "Hexadecimal in the outdoors"

#456.3 - Discussing Fomu with Tim Ansell and Sean Cross Sep 04, 2019

Show notes

Welcome Tim “Mithro” Ansell, Sean “Xobs” Cross and (returning co-host) Michael Ossmann!

Past guest appearances
- Tim Ansell on #375
- Michael Ossmann on #440.2 (at KiCon), among many other episodes (search for Michael Ossmann in past episodes)
Sean did the firmware on the Novena, an open source laptop he designed with Bunnie. We discussed this on episode #336.
Tim and Sean are working on the Fomu, discussed on the show after Chris took the workshop at Teardown.
Dave later was asking Chris about why open source and RISC V is relevant (on episode #449), which he struggled to voice. This episode discussed the relevance of these technologies.
There was a recent CS update about the Fomu going to camp, including a talk that Sean gave about the Fomu.

#456.2 - Crossover Camp with Hackaday and Unnamed Reverse Engineering Podcasts Sep 01, 2019

Show notes

We recorded this live at CCCamp 2019. The featured image is a shot of camp at night.
This crossover episode features the following two podcasts
- The Hackaday Podcast
- The Unnamed Reverse Engineering Podcast
With guests

#456.1 - An Interview with Schneider and Rahix of the Card10 Badge Team (CCCamp 2019) Aug 28, 2019

Show notes

Chris and Alvaro (UNRE), talked with Schneider and Rahix of the Card10 badge team at CCCamp 2019. This was the first of a few interviews done at camp.

Wiki page about the badge. It is assembled from two individual boards:
- The Fundamental Board
- The Harmonic Board
Schneider has worked on the past 2 badges
- Rad1o (2015)
- R0ket (2011)
Sensors on board:
- Temp, humidity, etc - BME680
- 9 axis, sensor fusion - BHI160
- Magnetometer - BMM150
- ECG - MAX30001
- Pulse sensor - MAX86150
Join the conversation on their IRC channel: freenode.net#card10badge

Thanks to @szczys for the picture of the badge!

Bill and Dave's Excellent Equipment Aug 19, 2019

Show notes

Dave reviewed the Vion multimeter...and was a bit underwhelmed.
What percentage of dev boards are used?
The multimeter chip
GPIB
Robby Newell shared a sweet testing setup
Lock in amplifiers
Raw research stuff
Jitter analyzer
$200 scope? Chris has a friend who claimed the DS1054Z is lower priced now.
Rigol rolled their own ASIC, the Phoenix chipset, doesn't have boxcar average
This is a rolling average after the ADC, higher ENOB
Why digital scopes look noisy
Jeri Ellsworth in her first Amp Hour interview said she wanted to skip the country after messing up a mask ROM
The US Navy will replace touchscreen controls
Dave interviewed John Kenney from Keysight (linked video is part 1 of 4)
Chris realized the parts he talked about in #453 were actually NCNR parts (non-cancellable non-returnable)
Returning parts
Ordering parts for long lead times
Shootout of 10 cent micros
It was actually the SDCC compiler for the 3 cent micro
GigaDevice parts (link to LCSC) are STM32 replacement components.
These are not exactly a new phenomenon, Dangerous Proto posted (a link to a site) about it nearly 2 years ago
Zeptobars also did a die shot of one of the parts

An Interview with MG (Mike Grover) Aug 12, 2019

Show notes

Welcome, MG (Mike Grover)!

Check out all of MG's exploits on his site mg.lol
There is a compilation video that is awesome/terrifying for all the things that cable implants can do
The "peanut gallery" during recording was Piotr and Joe Fitz.
- Joe FitzPatrick was a guest on episode 346
- Piotr has been a guest (or host!) on the following episodes:
  - 356
  - 409
  - 423
  - 440.2
  - 450
We were helping out with a training at Black Hat called Applied Physical Attacks 3 and 4
MG managed to use his mill with soldermask to get some really impressive results!
Including things like...BGAs! (holy crap)
The video about "hardware addiction"

Vertically Integrated Design Engineering Aug 05, 2019

Show notes

Chris is trying to making a remote controlled blinky thing for < $1
Dave suggested the Padouk $0.03 microcontroller, which now has a C compiler (read more about it on the EEVblog forum)
- (Chris later remembered Samy has a talk about lighting up balloons)
Mike Harrison on Embedded.fm discussing PICs
Switching costs
Chris will be at Chaos Camp this year!
Shahriar reviews the Deepace VNA
RF layout book
Difference from SI
Routing requirements
Spectrum analyzer
TI's Antenna Selection Guide
Where do we store files
Dave has been dealing with isolated power and data on usupply
Chris really enjoyed Kate Tempkin's talk about USB
TS80 can only power from USB quick charge and not PD
Dave giving a talk on solar roadways
Chris will be (is currently) helping past guest of the show Joe Fitzpatrick doing hardware training at Black Hat.
Alibaba is working on a homegrown chip based on the RISC V architecture
More focus on RISC V is a small silver lining of the trade war.
Russian chips from back in the day, 74 series
RISC V from scratch
Chris was on a 3M podcast talking about his excitement around RISC V and open toolchains.
LCSC is getting investment, which means its less interesting as a point of insight into Chinese branded chips..
Dave got back from celebrating the 50th anniversary of the Apollo 11 launch. He has been publishing videos over on his EEVdiscover channel.
Aria tracking planes
Dave and Chris did an episode while driving to Canberra to visit the DSN.
You can listen and watch along the Apollo 11 launch in "realtime"
Dave highly recommends watching the Apollo 11 movie at an iMAX.

Thanks to Suzanne Nilsson for the image of the ladder

An Interview with Kieran O'Leary Jul 29, 2019

Show notes

Welcome Kieran O’Leary, principal of Mixed Signal Systems!

Chris knows Kieran via the consulting forum. You can apply to join here.
Went to school in Cork, Ireland
Hard IP inside of FPGAs started on the Virtex2 pro
Now they're doing FPGA next to RF sections (which from a noise perspective is crazy)
FAEs vs AEs
"Applications engineers are responsible for shepherding the design from development into the customers hands"
AEs understand the need for trust with a customer
Kieran has worked at Xilinx, ADI and Wolfson
"If your client is pushing through a million units a week, it's a statistical certainty that any problem in the silicon is going to surface"
Sometimes you don't want the cutting edge silicon
"You want to be on the leading edge but not on the bleeding edge"
Making eval and dev kits at chip companies
Was it more about making a breakout board? Or something interesting?
Walking through silicon coming from the fab
Hand carrying the silicon back from the packaging facility
Pinouts move sometimes!
Custom sockets are expensive to make.
THD measurements might look poor if the connection between the socket and the device look bad
Boards for the general public need better supporting collateral
In 2012, Kieran decided to move into consulting
He often helps clean up technical debt on the hardware side of things
Things to watch out for in Signal Integrity
"Current flows in loops, either you or Maxwell will determine the return path"
Dr Howard Johnson on The Amp Hour
Split ground planes
"There's nothing foolproof to a sufficiently proficient fool"
Troubleshooting EMC problems
1. Check the values on the schematic
2. Take a nearfield probe and see what you see
3. Look for common culprits
  1. See where signals are jumping over a split plane
  2. Termination resistors in the wrong place
Helps to add placeholders for future filters and termination
Maxwell was Scotish, so there is a statue commemorating him. There is a Maxwell museum, as well!
Follow Kieran on Twitter!
His company Mixed Signal Systems is also on there.
Kieran helped run the EMC Compo 2015 - The 10th International Workshop on the EMC of Integrated Circuits
12th int'l is coming up in China

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