Shared Projects

This driver has an input range of 1.8V to 5.5V (so 1 cell LiIon or 2-3 1.2V-1.5V cells), and can supply an LED with a voltage between 1.2V and 5.5V. Maximum output current depends on the input and output voltage, but it can be calculated with a few formulas in the TPS63020 datasheet. Keep in mind, this driver has no low voltage cutoff! You have to check your battery voltage regularly!

There are 3 pads on this board. The middle one has to be shorted with one of the outer ones. This for the power save mode. Short it with the outer pad marked with “D” to disable it (>150mA), or short it with the other pad marked “E” to enable it (<=150mA).

For a parts list, look here: Budget Light Forum

The current can be programmed via one resistor R3. When the parts listed are used the formula is:

Resistance (R3) = (2000×I)/(0.5V-0.02Ω×I) (Current in A, Resistance in Ω)

Replace the “I” with your current you want. If you want a really low current , please change the current sense resistor (R1) to something bigger, and maybe change R2 as well.

To calculate current with your own parts, use this:

R3 = (R1×I×R2)/(0.5V-R1×I)

The OpAmp has to be chosen to fit the application. This depends on the input voltage range.

Some criterias to look out for:

• 20MHz bandwidth (depends on the amplification factor you have in your application, but 20MHz should be good for most things)

• Correct input voltage range

• Input offset, again depends… but <=500uV should be good

Important: Look out how the input voltage offset changes over temperature and changes in supply voltage! This should be low.

First test by Lexel - it works!

VUSB host https://www.instructables.com/id/ATtiny-V-USB-Project-Board/

SAMD21G18A Sensor Board with Color Oled

This Sensor Board is yet another variation of the other one on my site. It is not for sale with no real purpose in mind. It was created as design challenge. My full time job is pcb design work and as a hobby I enjoy experimenting with new design ideas. This was one of the more challenging designs I’ve worked on in a while. A few times I’d given up on routing it. Evan using four routing layers I found it tough. The idea was to hide the bezel of the display behind the board but have sensor components on that same board. It would look something like a little tiny television with all the components around the edges. This latest revision has fixed a few issues I found on previous versions but the design idea can possibly help others in some way. Full credit goes to Adafruit for publishing the Feather M0 design files along with the bootloader. I used the Feather design to create the schematic for my board. Credit also goes to Microwavemont on Tindie and the SSD1331 library that he has on his site compiles error free using the Arduino IDE.

The assembly instructions are at: https://0miker0.wordpress.com/samd21g-sensor-board-with-color-oled/

Feel free to email me at [email protected] with questions and follow me @mikerankin on twitter.

Rx module for musicFromMotion, as seen on calcium3000.wordpress.com

Adapter to fit a standard CR2032 in the HP 8756A.

Designed to fit Renata 701106 CR2032 holder, connection to the CPU board is via standard machined header pins.

https://i.imgur.com/8Gga0cc.jpg

Pogo programming jig for my MIL-STD-1553 board. Allows direct connection of the Lattice IDC cable without requiring real estate for a header on the PCB.

More details here: http://stevenmerrifield.com/1553/index.html

Lattice iCE40 Ultra FPGA generating MIL-STD-1553 BC/RT network messages.

More details here: http://stevenmerrifield.com/1553/index.html

NodeMCU breakout board with level shifter, external and DHT22 sensor connections. Project home: https://www.thingiverse.com/thing:2539897

A small line buffer for driving ws2801 LED strip from the SPI output of the raspberry. According to the datasheet of the WS2801 the data lines require 0.8*Vdd (= 4V for 5V led strings) for an input voltage to be considered as a high bit and the output of the RPI´s SPI is only 3.3 volt. Connections: 5volt dc jack in - USB-a out to power the pie or * :)

I use it for ambi-light / hyperion

Breakout board for the ATMega16m1, with 16 MHz crystal and CAN transceiver. Here’s the board on Github.

splitter board

nSOT cxn board with thru hole mmcx

Simple Light Following Robot with TIP31C transistors.

Prototyping board for esp32-d2wd. PCB antenna has not been tuned. https://github.com/lbernstone/esp32-d2wd

MarkusW’s smaller EHX Mistress PCB

Custom PCB for the LTC3106 (QFN-20) allowing its key features to be programmed by adjusting some Jumpers, the Potentiometers (VR1 and VR2) and the value of R2.

For better results, use 2 Layer 2oz 0.8mm Service

More details available in the IoT Energy Harvester using Cayenne project page.