‘Circuit Cobbling’ the Riffle Data Logger


John Keefe has designed an open source data logger that is able to monitor conductivity, temperature and turbidity of water in lakes and fits inside a plastic bottle.

The board is designed to monitor the conductivity (and, possibly, contamination) of water in lakes and streams, with the wonderful feature that it fits through the mouth of a regular water bottle. It’s called Riffle and it is the brainchild of Don Blair, who’s working with Public Lab and the MIT Center for Civic Media. This week I had the honor of working with Don at MIT.

‘Circuit Cobbling’ the Riffle Data Logger – [Link]

Get ready for MPLAB Express


Chas from iradan.com discuss about MPLAB Express, the new cloud IDE from Microchip for PIC microcontrollers. He writes:

I credit the maker movement with bringing electronics back from the crusty old and lonely electronics hobby back into the main stream. The Arduino is the micro of choice for this army of makers and I conceded it made sense… you install the IDE, plugged in your board into the USB port and a couple clicks later and you have an LED blinking.. the most exciting blinking LED you’d ever seen in most cases. I stuck with the PIC micros because I didn’t see any need to put back on the training wheels.

Get ready for MPLAB Express – [Link]

Monolithic linear battery charger operates from inputs up to 60V


Joshua Yee @ edn.com discuss about LTC4079 250mA Linear Li-Ion Charger IC that can be powered with voltages up to 60V.

For charging relatively low capacity batteries, or maintenance charging backup and keep-alive batteries, linear topology battery chargers are valued for their compact footprints, simplicity and affordability. Even so, there is a dearth of linear chargers that accept a 10V or higher input voltage, leaving many industrial and automotive systems underserved.

Monolithic linear battery charger operates from inputs up to 60V – [Link]

LT8391 – 60V Synchronous 4-Switch Buck-Boost LED Controller


The LT8391 is a synchronous 4-switch buck-boost LED controller that regulates LED current from input voltage above, below, or equal to the output voltage. The proprietary peak-buck peak-boost current mode control scheme allows adjustable and synchronizable 150kHz to 650kHz fixed frequency operation, or internal ±15% triangle spread spectrum operation for low EMI. With 4V to 60V input, 0V to 60V output, and seamless low noise transitions between operation regions, the LT8391 is ideal for LED driver and battery charger applications in automotive, industrial, and battery-powered systems.

LT8391 – 60V Synchronous 4-Switch Buck-Boost LED Controller – [Link]


Wireless communication between two Arduinos using inexpensive RF modules


Raj from Embedded Lab has posted a new article exploring an easy wireless communication setup between two Arduinos using low-cost ASK RF transmitter and receiver modules. He used a 433MHz Tx/Rx pair with two Arduino boards to illustrate how to construct a low-range wireless temperature and humidity monitor.

Wireless communication between two Arduinos using inexpensive RF modules – [Link]

AC PWM dimmer for Arduino


diy_bloke @ instructables.com has designed an AC PWM dimmer for Arduino:

Over 3 years ago, I published a simpel TRIAC AC dimmer for the arduino. That proved to be a very popular design. Yet in spite of the simplicity of the circuit the software needed was a bit complicated as it needed to keep track of the zero crossing of the AC signal, then keep track of the time and then finally open the TRIAC. So to avoid letting the arduino just wait for most of the time, an interrupt and a timer were necessary.

AC PWM dimmer for Arduino – [Link]


$2 Arduino – ATMEGA328 as a stand-alone


In this tutorial you will learn how to use ATMEGA328 microcontroller as standalone Arduino. This way you can minify your next arduino project.

They cost only 2 bucks, can do the same as your Arduino and make your projects extremely small.

We will cover the pin layout, how to make it ready for the Arduino software by burning a bootloader and how to upload sketches.

$2 Arduino – ATMEGA328 as a stand-alone – [Link]

BooSTick – small AA voltage booster


A single AA battery provides voltages of 5V or 3.3V for hardware prototyping.

This tiny board allows you to bring the power to your project, and not the other way around. Bring your micro to the sensor without running wires! A single AA battery is used to provide breadboard power of 5V or 3.3V (or other voltages by tuning the feedback resistors). A boost regulator provides the voltage.

BooSTick – small AA voltage booster – [Link]

5V to 12V Step Up DC-DC Converter


Step up DC-DC converter is based on LM2577-ADJ IC, this project provides 12V output using 5V input, maximum output load 800mA. The LM2577 are monolithic integrated circuits that provide all of the power and control functions for step-up (boost), fly back, and forward converter switching regulators. The device is available in three different output voltage versions: 12V, 15V, and adjustable.

Requiring a minimum number of external components, these regulators are cost effective, and simple to use. Listed in this data sheet are a family of standard inductors and fly back transformers designed to work with these switching regulators. Included on the chip is a 3.0A NPN switch and its associated protection circuitry, consisting of current and thermal limiting, and under voltage lockout. Other features include a 52 kHz fixed-frequency oscillator that requires no external components, a soft start mode to reduce in-rush current during start-up, and current mode control for improved rejection of input voltage and output load transients.


  • Requires Few External Components
  • Input 5V DC
  • Output 12V DC
  • Output Load 800mA
  • Current-mode Operation for Improved Transient Response, Line Regulation, and Current Limit
  • 52 kHz Internal Oscillator
  • Soft-start Function Reduces In-rush Current During Start-up
  • Output Switch Protected by Current Limit, Under-voltage Lockout, and Thermal Shutdown

5V to 12V Step Up DC-DC Converter – [Link]

MMC3630KJ – Magnetic sensor in BGA package

image: electronicsmaker.com

MEMSIC has announced the MMC3630KJ magnetometer that integrates a monolithic 3-axis AMR (anisotropic magnetoresistive) sensor and a signal conditioning ASIC into a 1.2 × 1.2 × 0.5-mm BGA package.

According to MEMSIC, devices in the series offer the ability to deliver a magnetic sensitivity in a range of ±30 Gauss and achieve a noise level that is five times better than other technologies.

The new sensor aims wearables and smartphones due to small size and low energy consumption. Device features include self-degaussing and a power-saving interrupt function.

MMC3630KJ – Magnetic sensor in BGA package – [Link]