Tuesday, July 9, 2013

Miniature MSP430 Programming Connector

The MSP430 is perfect for low-power and super miniature projects. Not only are smaller circuit boards cheaper to make, but they are desirable in many applications; such as in wireless sensor nodes, wearable electronics, and others. Standard 0.1" headers are simply too big for very small boards. To reduce the size requirement for the programming header, I have started using 0.05" headers. With this post, I would like to share how I use smaller headers to easily make my projects smaller and more cost efficient.



Due to how cheap the MSP430 LaunchPad is, it is often the best way to program your custom MSP430 boards. One of my earlier posts details how I use the LaunchPad to easily program custom boards using a 6 pin 0.1" header. It is important to me that I include both the UART RXD and TXD pins in the programming header for debugging purposes.


The simple schematic is shown above. Using a 3x2 pin 0.05" header on the target board, I created a "converter" board which connects to the LaunchPad using a 6 pin 0.1" header. Additionally, if I want to reduce the footprint further, I can use only a single 3x1 pin 0.05" header, ignoring the VCC, RXD, and TXD pins (as long as the target device is self powered).


The circuit board is shown above. It is very simple, yet very effective. The overall footprint of the programming header has been reduced significantly. Some possible improvements include the addition of a switch to allow you to choose if the device will be powered by the programmer or not, a protection diode for VCC, and a reset push button for those devices which are too small to have one. If you use the Eagle file provided below to make your own, please keep the URL to my blogs on the silkscreen.

Parts:

For almost no cost at all, you now have a miniature MSP430 programming header that you can use on all of your future projects. This concludes my small but useful post.