Are you making placement diagrams?

Wed, Mar 10, 21

Whenever I’ve needed to spin a circuit board these last few years, I’ve taken a bit of time early on in the process to make a placement diagram. I don’t know if this is an industry standard thing that I’ve just never heard of before, but seeing as I’ve never heard of it, I’d like to take this opportunity to coin the term “placement diagram”. A placement diagram is nothing special: it’s a block diagram, where each block represents a chip in a circuit layout, with sub blocks representing pin groupings on each chip. Lines drawn between each pin grouping represents IO connections, or buses between chips. The idea is to have a really simple representation of where each set of pins (power, data buses, DAC/ADC pins) breaks out on the chips in your layout, so you can plan for arranging them on a printed circuit board. This need not be super time consuming. For a simple two or four layer design, I can whip one out in an hour. For a larger board with multiple ICs, voltage regulators, and a higher layer count, it’s probably the work of a day.

PCB Verification Trick: Print Your Footprints!

Sat, Feb 27, 21

A useful trick taught to me by Florin Cocos (aka @voltlog) is to print out a sheet of paper set with new board footprints, and verify that your components fit their printed footprints, before ordering PCBs.

Keep Your Friends Closer

Thu, Jan 21, 21

Today’s post is a much sadder, much more personal one than I usually share. I learned yesterday that I lost one of my oldest friends to suicide. This is someone I have known since middle school. I know their whole family well. I won’t be any more specific than that out of respect for their surviving family, all of whom are grieving intensely at the moment.

Dave Chappelle's SNL Monologue is Awesome

Sat, Nov 14, 20

Biden’s victory speech last weekend was great. That is what the President of the United States should sound like. I’m really looking forward to that being the norm again. I don’t think Biden’s was the best televised address from last weekend, though. For me, that award goes to Dave Chappelle, and his opening monologue on Saturday Night Live.

Simulating the MXR Dyna Comp Compressor in LTSpice

Mon, Nov 02, 20

Compressors are another fun audio effect that I’ve been looking forward to taking a stab at simulating. In the spirit of starting small, I decided to take a look at the MXR Dyna Comp compressor pedal. It’s common, it’s affordable, and, as compressor circuits go, it’s pretty simple to understand. That’s saying something, as compression itself is a deep topic - far deeper than can be covered in this one blog post.

Alexa Seems to Be Getting Worse With Time

Tue, Oct 27, 20

I loved my Amazon Echo when they first came out. I love to cook, and I love to listen to music, so my Amazon Echo naturally won a spot in my kitchen when I first got it. Later on, it got upgraded to a Sonos One. Both speakers had voice control features that I loved, and used all the time. Hands-free timer setting and music control? Sign me up! However, Alexa’s shine has started to wear off - especially in the last six months. What’s changed?

What to Say When They Ask For Your Salary History

Mon, Oct 26, 20

TL;DR: “I’m still trying to establish whether this role is a good fit for me. Why? What is this role worth to your company?”

Simulating the Boss GE-7 Graphic Equalizer in LTSpice

Tue, Oct 20, 20

I find myself with a bit of excess time on my hands, now that I’m between jobs. Given that, I’ve found a few more challenging pedals to tear into and analyze.

How to do a Prototype Build for a Hardware Product

Fri, Oct 16, 20

Building your first set of product prototypes is a really exciting milestone for a hardware company. It’s the first chance to see the hard work of a lot of crossfunctional contributors bear fruit, in the form of a real, tangible, functioning item. It’s also a great opportunity to learn about the “meta-product” - the process of building your product at scale.

Simulating the Schaller Tremolo Pedal in LTSpice

Tue, Oct 13, 20

I’ve been on a roll with these pedal simulations, so, why not keep a good thing going? Today’s pedal sim is a closer look at the Schaller Tremolo Pedal.