Chris Gammell and Dave Jones' voices span the chasm of thousands of miles each and every week to speak to each other and industry experts about where the field of electronics is moving. Whether it be a late breaking story about a large semiconductor manufacturer, a new piece of must-have test equipment or just talking through recent issues with their circuit designs, Chris and Dave try to make electronics more accessible for the listeners. Most importantly, they try and make the field of electronics more fun. Guests range from advanced hobbyists working on exciting new projects up through C-level executives at a variety of relevant and innovative companies. Tune in to learn more about electronics and then join the conversation! Visit The Amp Hour website for our back catalog of 150+ episodes.
https://theamphour.com
#476 – An Interview with Kendall Castor-Perry
Welcome Kendall Castor-Perry, the Filter Wizard!
- Working on filters after high school and saw a “Wireman wanted” sign at Kemo.
- Stayed for 21 years, but got started sweeping the floors.
- Heath Robinson vs Rube Goldberg
- Learned out of databooks
- Where do you point people for filters?
- Not the Active Filter cookbook, though many would recommend it.
- Circuit theory courses online
- Starting with a scope
- Parents owned a big house, rented out rooms, tenants would need help with record players
- Moog’s ladder filter, which is a voltage controlled filter
- Kemo was general purpose lab instruments.
- Filters requirements were moving faster than the engineer knowledge.
- The days where you had to have filtering in front of a sampling ADC
- Moved to Burr Brown to work on DACs
- PCM1704
- Filtering at the front end is only if you want really want super low noise or if there is a wide bandwidth front end
- Broadly speaking the filtering has gone inside chips
- “My job has always been to chase signals around”
- A transducer is a piece of instantiated physics that turns a signal into a datastream
- “Think of me as the Van Helsing of electronic design”
- Information theory
- SERDES
- Using power supply instead of a voltage reference on DACs.
- Then Kendall went to work at Cypress Semiconductor (makers of the PSOC among other things)
- Doug Self
- Making your own resistor could be a source of distortion
- SPICE isn’t bound by physics
- Paul Rako
- When you add components you lose the systems thinking for your design
- Bob Pease skeptical of simulation (Paul wrote about what he really felt later)
- SAPWIN – symbolic analyzer
- FIR filter
- “Pessimal signal” (opposite of “optimal” because it’s pessimistic)
- KHN – state variable filter
- Prototyping using SPICE
- Karl Popper
- Disproof is the only thing the matters
- Eric Bogatin’s rules for engineers
- Different types of filters
- Monte Carlo analysis
- Cypress active in the USB Audio space…the microphone we sent to Kendall may have had a chip in it he helped design!
- Synchronous mode of USB audio
- Follow the #FilterWizard on LinkedIn (or follow his profile page) or check out his published articles on Planet Analog