About Colin Irwin

Colin is the chief designer at lagrangianpoint. His interests are in (too) many areas - to name a few: the Arduino platform, LED lighting, Software Defined Radio, statistics, trying to learn French, cooking and wine. Unfortunately lagrangianpoint isn't his day job just yet - but it's the plan. In the meantime he is Clinical Operations Manager for Cochlear EMEA. (Cochlear specialises in implantable hearing solutions for adults and children who are affected by deafness or hearing loss - check out www.cochlear.com)

Programmable DC load

For a while now I've been thinking "wouldn't it be nice to have a programmable DC load"... Something in the order of 30-50 V and a couple of amps. It appears that one only has to think the thought and it becomes available! Look no further than the MightyWatt module from Kaktus - www.tindie.com/products/Kaktus/mightywatt-kit-70w-electronic-load-for-arduino/   [...]

By |2017-03-29T23:21:34+01:00Friday, 6 November 2015|Builds|0 Comments

Programming the spark core

Some of the following material is basic operating information for the Spark Core - for example, see the Spark Core documentation page on Getting Started. Nonetheless, there's other material here which can be a little harder to find. And it's definitely useful for using / programming / doing whatever with the Spark Core. Prerequisites [...]

By |2017-02-04T18:43:54+01:00Wednesday, 13 May 2015|Tech Note|0 Comments

Eclipse IDE set-up for Spark Core

The development system which the spark team have created is interesting, and certainly works for quick testing of the Spark Core one has just purchased. However it's really not a true / professional development environment... Therefore the question of: if a more serious environment is requried, how should one proceed? It's definitely possible! With a little [...]

By |2017-02-04T18:43:35+01:00Saturday, 9 May 2015|Tech Note|0 Comments

Transformer IEC 61558 symbols and what they mean

Upon considering the design of the Isolated power supply design, a good question is what is the transformer IEC 61558 standard? In addition what do all the symbols mean? So a review the standard IEC 61558 Safety of power transformers, power supplies, reactors and similar products. This is the relevant standard for transformers of all types [...]

By |2019-01-13T00:24:39+01:00Saturday, 9 May 2015|Tech Note|0 Comments

Nixie controller communications

This Tech Note details the communications protocol for the Nixie Controller Supply. The controller is based on an ATmega 328P uC with communications via a standard RS-232 style serial link (+3.3 V high / 0 V low), at a speed up to 115200 bps. Message format Top level description Byte Description SOH Start of [...]

By |2017-02-04T19:32:50+01:00Thursday, 23 April 2015|Tech Note|0 Comments

Inrush current limiter – the solution?

In the last posting, relating to the design of an isolated power supply - Designing an isolation power supply - an inrush current limiter was identified to solve a problem... (There most definitely was! The 2 A slow blow fuses didn't stand a chance with the 300 VA toroidal transformer having a primary winding DC resistance of [...]

By |2018-05-07T22:07:31+01:00Thursday, 24 July 2014|Tech Note|0 Comments

Isolated power supply design – some considerations…

One piece of equipment that the lab has been lacking is an isolated power supply. Such a supply is useful for testing circuits/devices such that they're "isolated", as the name of course suggests. A good overview of why one might do / needs to do this is provided on Dave Jones' EEVBlog: EEVblog #279 – How [...]

By |2018-05-08T20:35:39+01:00Wednesday, 23 July 2014|Tech Note|0 Comments

xmem software library – Arduino Mega SRAM expansion

This xmem software library for the Arduino Mega SRAM expansion shield provides a simple C/C++ interface to access the additional memory provided by the shield. The library interface itself is quite simple, but still provides for powerful memory management of the additional 448 kB memory in one of two modes. Direct memory access or compiler [...]

By |2018-05-08T20:35:45+01:00Saturday, 26 April 2014|Software|0 Comments