Shared Projects by PeskyProducts

Wi2Wi W2SG0008i 1.575MHz GPS module add-on shield for Teensy 3.1. A mechanical switch toggles between UART and I2C output; 4K7 pullup resistors are on the SDA/SCL lines. Solder jumpers can be used to choose 4800 (default), 9600, and 38400 BAUD rates for NMEA protocol output to UART on Teensy Serial2, I2C supports both 100 kHz and 400 kHz rates. Solder jumpers can be used to take power and ground from the board edge transforming the shield into a conventional breakout board for breadboard use. The shield was designed for the 3V3 VIN of the Teensy but the LDK130 1.8V voltage regulator required by the GPS module can take up to 5.5V as input, making the shield in breakout-board mode ideal for any Arduino platform, even the Arduino UNO. The serial and I2C signals are logic level translated up to VIN on output from the board and down to the 1.8 V of the GPS module’s digital IO on input. There is a small SPDT button switch that sends the required ON/OFF signal to the GPS module. The passive chip antenna placement is less than perfect since it lacks a sufficiently ground-shielded feed line, which is not really wide enough to make the 50 Ohm needed. This is a compromise for the small size of the board, which allows the add-on function without overwhelming the Teensy form factor.

nRF24L01+ 2.4 GHz radio add-on board for Teensy 3.1 with smaller 16 MHz crystal and improved in-board antenna instead of low-range ceramic antenna

MPU9250 9-axis motion sensor + MS5637 Altimeter for mounting on the back pads of Teensy 3.1. Removed back plane ground beneath MPU9250 to reduce magnetometer interference.

ST Microelectronics' newest 9-axis motion sensor the LSM9DS1 plus Measurement Specialties' MS5611 pressure sensor with hardwired I2C. The board is designed to be either a mini Teensy 3.1 add-on board with SDA/SCL on pins 17/16 and power taken at the Teensy end, or the solder jumpers on the back can allow power to be taken from the edge of the board for convenient breadboarding like a traditional breakout board. The board is designed in mini-add-on mode to keep the hardware SPI pins free for other add-ons like an SD card or rf radio that must use SPI. One interrupt each from the accel, gyro, and mag is broken out and solder jumpers can allow access to the other two interrupts, if desired. Solder jumper can also be used to change the address of the LSM9DS1. Removed ground plane in LSM9DS1 sensor footprint to reduce interference with magnetometer.

LSM9DS0 9-axis motion sensor plus MS5637 pressure sensor micro add-on for Teensy 3.1 with hardwired I2C. Removed ground plane beneath LSM9DS0 per ST Microelectronics' recommendation to avoid squirrely magnetometer readings. Also moved traces as far as possible from sensor in an effort to reduce interference with the mag. Is it enough?