Marc's open source hardware activities

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Every LPC-base PCB I build so far is programmed using the UART-ISP-protocol. As I'm biased toward mains voltage applications like motor inverters and high power switch mode power supplies, I need a galvanic insulation between the microcontroller/power stage and the PC used for programming. GIM3b does exactly that: It provides 3.3V level UART plus /RESET and /BOOT signals and provides over 500V potential difference between USB levels and microcontroller GND. Have a look at GIM3b schematic and GIM3b board

Connectors are USB-Mini-B and MicroMatch-6 (1.27mm ribbon cable pitch, 6-way). If you really need one, please contact me. I would sell for 30EUR or so.


Invcore1 schematic and InvCore1 board
Invcore1 is a LPC213x based board that serves as controlling unit for many projects. Invcore1 is designed using halogen-free, lead-free and beryllium-free components besides being RoHS-compliant. All (1.27mm pitch) ribbon cable connectors are MicroMatch (or MiniModule from Wuerth Electronics). Power supply is a WAGO-2060-2 clamp. Interfaces: Invcore1 is lacking a true double-edge-controlled 3-phase (or even 2-phase) PWM.This can be achieved with a LPC176x device. It turns out that most applications I wanted to implement do not need that. The LPC2100 family is easy to use - less clocking complexity, not that much power-saving possibilities, lower pin-count. And: I do like the 32-bit ARM instruction set for assembly language!
If you have a closer look at the LPC213x pin-out and the LPC175x/176x pin-out you will notice, that LPC213x has a much heavier focus on ADCs than LPC17 - which is important for the applications I have in mind. So I believe, LPC213x is the better choice for all but 3-phase applications well above 600V bus voltage. I'm working with the LPC families LPC21xx, LPC23xx, LPC175x, LPC176x, LPC11xx, LPC81x - my decision is not based on the habit to use a specific core, really.

Invcore1 is augmented by the following connectable components:

Most components were designed in 2013, software development started in 2013. The primary goal was Zn-plating of steel parts and plasma-electrolytic oxidation. However, software development soon targeted on re-usable modules for all kinds of applications mentioned below and proper user-interface design was soon recognized essential to the stand-alone usability of the system.

This set of PCBs paired with the cool software I created represent the building blocks of many interesting applications:

Last edit: 2013-11-08.