A Cost-efficient Super-Cascode SiC Switch

Coping with rapid technological advances and finding efficient energy solutions are the keys for development of power electronics of the future. A new research had been done in North Carolina State University about increasing the efficiency of high-power switches.

Silicon Carbide is a compound of silicon and carbon with chemical formula SiC. It is a wide bandgap (WBG) semiconductor, that allows devices to operate at much higher voltages, frequencies and temperatures than conventional semiconductor materials.

Researchers came up with a high voltage and high frequency silicon carbide (SiC) power switch that could cost much less than similarly rated SiC power switches. This research may guide to new applications in power converters like medium voltage drives, solid state transformers and high voltage transmissions and circuit breakers.

Semiconductor devices like the 15kV SiC MOSFET can lead to great potential applications in high voltage and high frequency power converters. However, these devices are not commercially available and their high cost displaces them from industry competition with other alternatives like the standard IGBT (Insulated-gate Bipolar Transistors) that are widely used, but in the same time they dissipate a lot of energy while switching on and off.

Loss Comparison between Silicon IGBT and SiC MOSFETs
Loss Comparison between Silicon IGBT and SiC MOSFETs

The new SiC power switch, called FREEDM Super-Cascode Switch, contains a series of 1.2kV SiC power devices to produce a 15 kV and 40 mA output that can transcend the 15 kV SiC MOSFET in ease of adoption and cost – since it costs only one third of the estimated high voltage SiC MOSFETs. In addition, this new switch is capable of operating in a wide range of temperatures and frequencies due to its proficiency in heat dissipation, which is considered an advantage in power devices.

FREEDM Super-Cascode SiC Switch
FREEDM Super-Cascode SiC Switch

Since there is no high voltage SiC device commercially available at voltage higher than 1.7 kV, as Alex Huang said – Progress Energy Distinguished Professor, he assures that this solution paves the way for power switches to be developed in large quantities with breakdown voltages from 2.4 kV to 15 kV.

The research took place in North Carolina State’s FREEDM Systems Center which is funded by National Science Foundation. This center’s mission is to modernize the electric grid and mold the generation of leaders by providing all the needed software and hardware tools, funds, and partnerships with Industries. This project had also participated in IEEE Energy Conversion Conference & Expo on September 2016 and it was presented by Xiaoqing Song, a Ph.D. candidate at the FREEDM Systems Center under Huang’s supervision.

More research projects in the same field can be reached at the FREEDM Systems Center website and further details can be found at the university website.

Via: ScienceDaily

$18 RTC Shield For Both Arduino UNO And Raspberry Pi 3

Time and date information may be essential requirements for developing a hardware project, such as registration systems, alarms, and smart pills box. These information can be obtained locally by RTC (Real Time Clock) and RTCC (Real Time Clock Calendar) circuits like DS1307 from Maxim Integrated.

Microchip, an embedded control solutions company, produced MCP7941X three-member family of low power RTCCs with EEPROM and SRAM. Each of MCP79411 and MCP79412 has a unique MAC address that can be programmed by the end user for the networking applications. MCP79411 uses 48-bit MAC address and MCP79412 uses 64-bit one. MCP79410 is suitable for non-network applications as it has the same features except the unique ID.

These integrated circuits are compatible with I2C™, include a battery switchover circuit for backup power, and use a low-cost 32.768 kHz crystal, providing time tracking in 12 or 24 hour format and two settable alarms to the second, minute, hour, day of the week, date or month. They also have programmable output pin which can be set as an alarm out or a selected frequency clock out.

MCP79410 Integrated Circuit
MCP79410 Integrated Circuit

MCP79410 has the following features:

  • Battery-Backed Real-Time Clock/Calendar (RTCC) with configuration of Hours, Minutes, Seconds, Day of Week, Day, Month, Year in 12/24 hour modes
  • Leap year compensated  to 2399
  • On-Chip Digital Trimming/Calibration with 1 PPM resolution and ±129 PPM range
  • Dual programmable alarms
  • Versatile output pin
    • Clock output with selectable frequency
    • Alarm output
    • General Purpose output
  • Power-Fail Time-Stamp, time logged on switchover to and from Battery Backup
  • 2-Wire serial interface, I2C™ compatible, clock frequency up to 400 kHz
  • 64 bytes battery-backed SRAM and 1Kb EEPROM memory user memory
  • 64-bit protected EEPROM area, robust write unlock sequence
  • Wide voltage range, operating voltage 1.8V to 5.5V and backup voltage 1.3V to 5.5V
  • Low Typical Timekeeping Current
  • Automatic Switchover to Battery Backup
MCP79410 Box Diagram
MCP79410 Box Diagram

Based on MCP79410, Futura Group Srl developed a RTC shield compatible with Arduino UNO and Raspberry Pi 3 Model B and it supports all of the functions needed to manage the MCP79410 circuit.

The shield PCB contains the MCP79410 chip, SMD components, CR2032 battery holder, male and female stripps, and three buttons. The three buttons are connected with the Arduino and Raspberry Pi and they are used for the configuration process.

The RTC Shield
The RTC Shield

There is also a library which allows you to use and program the shield easily. It contains three files, two of them are the functions and theirs declarations, and the third is a text file contains the keywords of public functions and theirs usage.

The shield is available for $18.5 (16.50€). You can order it from open-electronics store and have access to the libraries and example sketches.

Full documentation of the shield with its schematics and diagrams is available here.

Deltu, An Interactive Delta Robot

Robots intelligence is going beyond borders and it may outsmart humans in some common games. Right now, these robots have their own personalities and if you are not skilled enough, they might get upset with you!

The interactive Delta three-arm robot, Deltu, is able to interact with humans. This Interactive design consists of 3 arms, an Arduino mind, a ‘personality’, and two iPads that run Unity3d applications. A HTTP request is send to the computer by the human’s application and then a Python server sends strings and commands to Arduino for controlling the robot.


Deltu uses three different applications using symmetry as an interpretation, a mirror and a reflection of our own image. The first game “Together” is a drawing game where Deltu imitates and interprets what we draw. The second one is a battle between the machine and the human. And the final third one is a memory game where the human must learn from the robot. These games were designed to emphasize the special relationship with robots and its evolution.


Deltu uses two iPads to play mimicking games with a human opponent. This sounds amazing – until you know that Deltu is very demanding. Once the opponent makes a mistake, it may stop and take selfies or browse apps. The robot creates patterns by pressing particular tiles on an iPad. If the movements are not mimed precisely, it will shake its adjoined arms in a side-to-side motion that appears to simulate frustration. Then, the robot exits the game and opens the camera app instead.It snaps a few photos of itself and uploads these to Instagram. It even takes a few moments to browse the Explore section and follow a new account, and looks through SoundCloud.

To understand how the robot would work, check it in action

According to the creators, the project explores the relationship between humans and artificial intelligence, as the role of these systems in society has not yet been defined.

This relationship is not only making our performance better, also it may become a source of learning. Currently, this project only supports iOS and works on iPads.

Deltu Interactive designer, Alexia Léchot, had also created other interactive games during her graduate study in ECAL – University of Art and Design in Lausanne, Switzerland.

Via : Arduino Blog

ESP8266 GMail sender


Borya shows us how to send emails using an ESP8266 wifi module.

I will show you how to send emails from any ESP8266 wifi module using Gmail server.

This instructable relies on Arduino core for ESP8266 WiFi chip,

which makes a self-contained microcontroller from it (no need of AT commands and master devices).

ESP8266 GMail sender – [Link]

40 PIN & 28 PIN PIC18F USB Development Board


PIC18F USB Development Board will help you with your prototyping requirement with any 28/40-pin Microchip microcontroller supporting USB interface . The board has been tested using PIC18F4550 40 Pin & PIC18F2550 28 Pin Microcontrollers.


  • All ports terminating in separate Box Header with 5 VDC source option
  • ICSP connector for programming for the PIC’s with ICD support
  • Bridge in the input provides any polarity DC supply connection to the board
  • 20 MHz crystal source
  • Onboard +5V Voltage regulator
  • Four mounting holes of 3.2 mm each
  • PCB dimensions 77 mm x 87 mm

40 PIN & 28 PIN PIC18F USB Development Board – [Link]

Tibbo – MQTT Library Demo


Tibbo created two small programs that illustrate how easy it is to write MQTT-enabled apps in Tibbo BASIC or Tibbo C.

To illustrate the use of the MQTT library, we have created two simple Tibbo BASIC applications called “mqtt_publisher” and “mqtt_subscriber”.

In our MQTT demo, the publisher device is monitoring three buttons (Tibbits #38). This is done through the keypad (kp.) object.

The three buttons on the publisher device correspond to the red, yellow, and green LEDs (Tibbits #39) on the subscriber device.

As buttons are pushed and released, the publisher device calls mqtt_publish() with topics “LED/Red”, “LED/Green”, and “LED/Red”. Each topic’s data is either 0 for “button released” or 1 for “button pressed”. The related code is in the on_kp() event handler.

The subscriber device subscribes to all three topics with a single call to mqtt_sub() and the line “LED/#”. This is done once, inside callback_mqtt_connect_ok().

With every notification message received from the server, the subscriber device gets callback_mqtt_notif() invoked. The LEDs are turned on and off inside this functions’s body. (more…)

40 Pin & 28 Pin dsPIC Development Board


The dsPIC Development board has been designed mainly for Motor dsPIC30F4011 Digital Signal Controller in the 40-pin motor control socket and dsPIC30F4012 28 Pin digital signal controller, the board can also be used with other dsPIC ICs. Board provided with 3.3V and 5V regulator, crystal oscillators and a programming connector. In addition, the board is populated with dual header connector for all I/O, reverse supply protection diode, onboard 3.3V & 5V LED, Screw terminal for supply input, push button switch for reset, 6 pin header connector for programming, serial communication  header connector, jumpers for multi serial communication option , electrolytic capacitor for filters. Optional provision for LM317T TO220 Regulator for 3.3V and 5V and Jumper for 3.3V or 5V power supply selection to power up the dsPIC.

40 Pin & 28 Pin dsPIC Development Board – [Link]

18 PIN PIC Development Board with Header IO


PIC16F 18-pin Development Board will help you with your prototyping. It works with any of Microchip’s 18 pin of 16F PIC microcontroller.


  • All ports terminating in separate box header with 5 VDC source option
  •  ICSP connector for programming for the PIC’s with ICD support
  •  Jumper selectable on board pull up resistor for PortA.4 pin on the microcontroller
  •  Bridge in the input provides any polarity DC supply connection to the board
  •  Jumper selectable 20 MHz crystal source
  •  Onboard +5V Voltage regulator
  •  Four mounting holes of 3.2 mm each
  •  PCB dimensions 56 mm x 55 mm

18 PIN PIC Development Board with Header IO – [Link]


PIC16F 28-pin Development Board with LCD


This development board offers various important add-ons which we considered are important to a developer of Microcontroller based project from Microchip.


  • This board can be used with any of the 16F / 28 Pin PIC ICs compatible with 16F73 MCU. This kit is supplied with a PIC 16F73 MCU for development purposes.
  • The Clock frequency to the MCU is a 4 Mhz Crystal
  • This Development Board offers a ICSP connector for easy download of your code onto the MCU. Resistor R1 and Diode D1 Offer protection of Programming voltage interfering with the Supply voltage.
  • A 16×2 Backlight LCD helps as a displays of data in your project. PR1 controls the Contrast of the LCD.

PIC16F 28-pin Development Board with LCD – [Link]

Raspberry Pi RF frequency counter


A Raspberry PI RF frequency counter project from Scott Harden, that is available on GitHub:

Raspberry PI RF Frequency Counter with Python Interface. The RF signal clocks a 32-bit counter (SN74LV8154) connected to a 16-bit IO expander (MCP23017) accessable to the Raspberry Pi (via I²C) to provide real-time frequency measurements from a python script.

Raspberry Pi RF frequency counter – [Link]