Shared Projects by PeskyProducts

Simple circuit using LCM555 timer for clock to operate SN54LV163A binary 1 - 7 counter which drives FFB3904 dual mosfets that control two rgb LEDs which, lastly, cause the owl’s eyes to glow with continuously varying color. Intended as a wearable pendant for little girls and daring men. Added SMD switch for power on/off. Added rechargeable 3V, 3.4 mAH coin cell Li-ion battery and charging circuit. Removed through-hole JST connector. Added top hole for keychain.

ST Microelectronic’s ultra-low-power real time clock coupled with Bosch’s BME280 pressure, humidity, 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 Comchip low forward voltage Schottky 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 18 hours. The board is now a tiny weather logging station: pressure, temperature, and humidity can be logged once per minute for 15 days! Changed IRQ so pullup voltage provided on RTC side of the diode.

MPU6500 6-axis motion sensor plus AK8963C magnetometer plus BMP280 pressure sensor with the SENtral EM7180 sensor fusion hub with M24512DFC EEPROM to store the SENtral configuration file. SENtral takes 9-axis accel/gyro/mag data from MPU6500 and AK8963C and performs hardware sensor fusion returning raw data, quaternions, linear acceleration, and heading, etc. Breakout board using the SENtral with jumpers to take power from edge pins for breadboard use or to mount directly on the Teensy 3.1 for comparison between open-source software sensor fusion and the hardware sensor fusion provided by the SENtral. SENtral can act as master to BMP280 pressure sensor and in the future include the pressure data in the sensor fusion.

Nordic Semiconductor’s low-power 2.4 GHz RF radio with pcb antenna and matching circuit per Nordic’s spec. Using much smaller XRCHA16MHz Murata crystal to reduce cost and board size. Added solder jumpers on back to allow 3V3 and GND to be taken from board edge to make breadboard friendly.

D203S PIR signal processed by BISS0001 active only when photoresistor detects dark ambient conditions. PIR detection triggers 2600 mcd white led with 160 degree illumination for a time settable by a Murata potentiometer. Slide switch chooses between retrigger modes. In addition to the usual motion-activated illumination, the trigger signal from the BISS0001 is pinned out to the side of the board so other actions can be triggered such as camera control, relays, etc. Intended to be attached to a 9V battery for a compact motion controlled solution with the TI TPS714XX voltage regulator providing either 3V3 (here) or 5 V depending on the application.