Solving “range anxiety” problem for my smartphone (well, almost)

As some of you know, I’ve recently traveled to Boston for the ESC/Design East conference. While that was fun, what quickly became a problem was my phone’s limited battery life. I’d leave in the morning with full charge, and by about 4PM each day it’d be asking for a charger. Normally it’s not a problem, except when you are in a new city and relying on your phone as a your navigation aid. There are obviously commercial solutions- a spare battery or a rechargeable battery pack or theOSHW ones such as Adafruit’s MintyBoost.  MintyBoost was the closest to what I was looking for, but still not quite it. So I set out to make my own. Continue reading

Seagate FreeAgent Theater+ USB debug

It appears there is no end to things breaking and ending up in Kuzyatech lab. Today’s patient is a Seagate FreeAgent Theater+ media streaming box that decided to stop noticing USB drives. The box is a nice little device that can play audio and video content from the network or from one of the three local USB ports: front, rear or a dock-like middle one that’s used to connect Seagate’s own portable hard drive. Both front and back ports were dead. Well, time to take it apart! Continue reading

ESC Boston / Design East pictures

I’ve just returned from Boston, where I poked my nose into Design East/Embedded Systems Conference. This was a very brief stop, limited to expo floor and panel discussions

Part of the week: NSI450xx family of CCR from OnSemi

This week’s find is a NSI450xx/NSI500xx family of parts from On Semiconductor. It’s a two terminal constant current regulator (CCR) offered in SOD-123,SOT-223 , SMB, SMC and all the way to DPAK cases. The device can handle 45V surges and regulates current to 15-350 mA depending on the individual part number. This makes it very convenient to insert into LED strings and have them stay in regulation and constant brightness with variable input voltage. Continue reading

Innolux BT156GW01 TFT LCD Panel teardown

I’ve always wanted to see what the latest LCD panels look like inside, and such a chance just presented itself. I got my hands on a broken 15.6″ panel, used in many laptops these days. This particuar one had DP/N number on it, so I assume it was used in a Dell. Let us see how much we can learn looking at the design with limited access to device datasheets.

Innolux BT156GW

Continue reading

Atmel QTouch tuning using Saleae Logic16

I happened to use an Atmel Qtouch chip in a project recently. The particular part was AT42QT1040, used in a fairly typical application- replacing four tactile buttons with four touch buttons. The chip is literally a “black box” that you give power, connect a few passives to the electrodes and in return you get four digital outputs representing the status of each key. No software to write, and is very simple. This particular feature came up very handy when a customer recently decided to switch from tactile to touch buttons mid-design. Since I was using Altium Designer on this project, the electrodes were essentially a freebie for me. I simply used Atmel Qtouch library, added the rectangular buttons into my schematic as components and Continue reading

DipTrace layout and ordering boards from Dorkbot aka OSH Park

Well, my test design is complete and now I need a few prototypes to play with. The usual ways of ordering PCBs are rather expensive, with just tooling fees in hundreds of dollars. The remaining options are a few China based places such as Itead Studio, Seeed Studio ,PCB Pool and Batch PCB ran by Sparkfun, and an OSH Park ran by Laen from Dorkbot. He runs a community PCB service that groups orders and orders them periodically on a common panel, sharing costs between all people. The cost is very reasonable ($5 a square inch) and you get three boards. So a 2 square inches board in three copies will cost you $10 delivered from a US based board house! That definitely opens the door for quick prototyping of pretty much anything! After having used other company’s prototyping services, I must say OSH is also by far the most user friendly. Lets walk through the steps of ordering these boards. Continue reading

Blog update and some musings on EDA tools

Blog updates

Small blog updates this week. The sidebar is now present on all posts, not just the front page for easier navigation. The awesome picture of the Fluke board has now earned its spot as a blog header.I call it the “dancing transistors” banner. Sure beats stock image.

EDA tools choices

In more electronics related news, I’ve been working on a simple board using DipTrace. It’s a new tool for me, so a small simple design/layout and board order will test the waters so to speak. Why DipTrace you might ask, considering I already use high end packages at work such as Mentor Graphics Pads and Altium Designer, or how about Eagle?  Well, for starters my hobby budget is small, and licensing Altium or Pads is well outside of it. I could potentially use Eagle, like everybody else does in the open hardware community, except for two things. Number one, I absolutely could not stand it when I tried it, and number two- the pricing structure is a bit silly. You either get a light version with 2 layers and a lot of limitations for $69, a Standard version for sch+layout for $575 or a professional for $1145. Sure, one could get a hobbyist/non profit version for $169 but first you have to sign a declaration that makes you liable the moment you design a board and sell a couple. Meh, not good enough. And at every level of pricing, there is still a board size limit. Enter DipTrace. The  free/noncommercial license allows 500 pins and 2 layers. For a commercial version, Standard version with 1000 pins and 4 layers is only $345 and the full version with no limitations is $695. There is also an intermediate version that’s $495 and goes up to 6 layers. That to me seems like a much nicer upgrade path should I ever want to design and sell products. The fact that you could just pay the difference in price to go up the feature ladder is very smart as well.

Now back to work. Pictures/board info coming soon

Sinclair PDM35 multimeter teardown

Another Hamfest find is the Sinclair Radionics PDM 35 digital multimeter. Having grown up with ZX Sinclair Spectrum clone, and reading a lot about Sir Clive Sinclair and his creation I wasn’t about to walk by this. If the look of it is a bit calculator-like, that’s because they actually reused a calculator enclosure! This was a  cheap model, selling for 33 pounds in the 70-s and 80s

It's a calcu-err-meter

Continue reading