Shared Projects

Nanoscopic breakout board for MPU9250 motion sensor hardwired for I2C and ADO=1 to serve as auxiliary motion sensor to support more conventional Mini and/or Micro add-on boards when one MPU9250 just isn’t enough. I2C pullup resistors can be added if they are the only ones in the circuit; usually these will be unoccupied.

Inifinite Noise true random number generator with pads for soldering USB pins to the board. Buy the pins from Jameco, part #230965

ST Microelectronic’s ultra-low-power real time clock coupled with Measurement Specialties MS5637 pressure and temperature sensor and ST’s M2402DFC 2Mbit EEPROM in an appallingly small add-on board for Teensy 3.1. Power is supplied via digital write to general GPIO pins since the total power requirement never exceeds 2 mA. Communication is via I2C and there are 4K7 pullup resistors on board. The temperature sensor allows the Teensy 3.1 microcontroller to make periodic calibration updates to the RTC calibration register so the clock remains temperature compensated for maximum (~2 ppm or 1 minute a year) accuracy. The clock outputs the usual date, days, hours, minutes, etc. but also outputs tenths of seconds as well as hundredths of a second.The on-board EEPROM is useful for data logging and storing alarm patterns (music) for output to a small speaker. With 2 Mbits (256 kBytes), lots of data can be logged and dozens of alarm sounds can be stored; one for every occasion! Added Taiyo Yuden PAS3225 2.6V 14 mF super capacitor and 1N4148 diode to provide power to the RTC time keeper even when disconnected from the microcontroller. The PAS3225 5 microAhour super cap can run the RTC (which needs ~330 nA at 2.6 V) for about 15 hours. Added ST Microelectronics' HTS221 16-bit, ultra-low-power relative humidity sensor. The board is now a tiny weather logging station: pressure, temperature, and humidity can be logged once per minute for 15 days!

BMX-055 9-axis motion sensor and MS5637 pressure sensor add-on for teensy 3.1 with hardwired I2C. Added solder jumpers on back of board so 3V3 and GND can be taken from the board edge for better breadboard use.

ATtiny [2,4,8]4 micro + ESP8266 Wifi. All I/O 5V tolerant. About the size of an AA battery (with a socket on the back). AtTiny can shut down the power rails to the ESP8266 completely for ultra-low power consumption

74AC04 buffer for Jackson Labs LTE-Lite

Based on Said Jackson’s suggested design described on the time-nuts email list.

Built board

Schematic

Apologies for poor silk screen; parts libraries need work.

C1-4: 0.1uF 1206 X7R

C5: 0.01uF 1206 X7R

C6: 10uF 35V Tantalum (< 3 ohms ESR, +ve to the right, e.g. Kemet T491D106M035AT)

C7: 1uF 1206 X7R or Tantalum (+ve to the left, e.g. Kemet T491A105K035AT )

D1: RS1B-E3 or similar

IC1: 74AC04 SOIC

IC2: LT1763CS8-3.3 (pin 1 top left)

X1-4: SMA-F end launch or solder coax directly.

J1: 2-pin header

R1-6: 100 1206

R7: 1M 1206

MMBT5179 HF amplifier

cpu replacement for kinesis keyboard

breakout board for bidirectional level shifter

Ultra low voltage input switching DC converter with LiPo charger and 2.5V system voltage. The KiCad files and BOM are on my site: prjct.net

DIY LTX RapidFire!

ECE 4760 Project Board

NRF24 nitwork node with ATTiny841, LM92 or DS1621 temperature sensor, 3.3V regulator. It uses ISPogo landing pads for in-system programming.

This board is designed to fit in a Hammond 1551P case, 40x40x20mm. The board has space for a CR2032 battery on the bottom.

The NRF24 only fits in the box if it is soldered down directly, but using the header and a socket works fine outside this box.

ARM development made easy. OSH, fully featured IDE, Mac OSX Linux and Windows support, programmers and adapters not needed, ready to use out of your reflow toaster oven. Full documentation here https://github.com/zapta/arm/tree/master/pro-mini (scroll down that page).

7 RGB LED Pendant powered by an ATTINY85. Displays a plethora of animations in a package you can wear around your neck. Exposes 6 pin ICSP headers for reprogramming and supports recharging over USB.

More Info: https://github.com/Squeegy/ChakraPendant

SNES CiClone KEY PCB with ICSP

More info can be found here https://facelesstech.wordpress.com/2015/02/07/lets-get-atmega_drunk/

Bridgeable Stereo Amp using L165/LM383/LM1875/TDA2002/TDA2003/TDA2040 +80Hz lowpass filter. Split or single supplies Use datasheet for config guide. [email protected]

LDR and Gain