24-48V to 5V – 3A DC-DC Converter

24-48V input voltage range 3A output current DC-DC Converter using BD9G341AEFJ IC from ROHM semiconductor. This IC is ideal for high voltage to low voltage converter with 3A output current. Pin configuration of the board with 3 Pin horizontal mounting of the regulator is similar to LM7805 LDO regulator and is suitable to use this IC as replacement which can provide more current and take high voltage input.

Different voltage output are possible by changing few components. Refer to datasheet for the same. Example circuit can provide 5.1V/3A with input supply range 24-48V DC and operating frequency 200 KHz.

24-48V to 5V – 3A DC-DC Converter – Link

OwnCloud on Raspberry Pi

Install OwnCloud on Raspberry Pi And make your own cloud server.

OwnCloud set on Raspberry Pi can be a good example of smart cloud storage. A cloud storage is a cloud computing model in which the data is stored on remote servers and maintained by a cloud storage service provider. This allows users to customize their data and share it with friends and business partners over the Internet.

OwnCloud as cloud storage server is a great opportunity, especially for those who would like to use OwnCloud on Raspberry Pi (or any other ARM device).

OwnCloud on Raspberry Pi – [Link]

Researchers Developed New Efficient, Thin, and Flexible Cooling Device

Engineers and scientists from the UCLA Henry Samueli School of Engineering and Applied Science and SRI International, California, have created a thin flexible device that could keep smartphones and laptop computers cool and prevent overheating. The component is based on the electrocaloric effect – a phenomenon where the temperature of material changes when an electric field is applied to it. The research has been published in Science.

Thin, flexible cooling device
Thin, flexible cooling device

The system’s flexibility also allows it to be used in wearable electronics, robotic systems, and new types of personalized cooling systems. It is the first demonstration of a solid-state cooling device based on the electrocaloric effect. The method devised by UCLA and SRI researchers is very energy-efficient. It uses a thin polymer film that transfers heat from the heat source – a battery or a processor – to a heat sink, and alternates contact between the two by switching on and off the electric voltage.

Because the polymer film is very flexible, the system can be used in devices with complex shapes or moving surfaces. Body tracking wearable devices can easily accommodate this flexible cooling device. Such cooling pad could keep a person comfortable in a hot office and thus lower the electricity consumption for air conditioning. Or it could be placed in a shoe to keep a runner comfortable while running in the sun. It’s like a personal air conditioner.

The tendency of flexible electronics to overheat remains a major challenge for engineers. The cooling systems in larger devices like air conditioners and refrigerators, which use vapor compression, are just too large for mobile electronics. The new cooling device produces a specific cooling power of 2.8 watts per gram and a COP of 13. This is more efficient and compact than the existing surface-mountable solid-state cooling technologies, opening a path to using the technology for a variety of practical applications.

Roy Kornbluh, an SRI research engineer, said,

The development of practical efficient cooling systems that do not use chemical coolants that are potent greenhouse gases is becoming even more important as developing nations increase their use of air conditioning.

Arduino Two-Way Bluetooth Communication Tutorial

Welcome to another Arduino Tutorial! Today we are going to learn how to use Bluetooth to exchange data between two Arduino boards! As a demonstration project, we are going to build a simple weather station. There is a lot to cover so let’s get started!

Arduino Two-Way Bluetooth Communication Tutorial – [Link]

Design and Implementation of a 12 Lead Portable ECG

Alex Lao and his team at McMaster University have developed a compact, battery powered, 12-lead electro-cardiogram:

During the academic year of 2016-2017 at McMaster University, in conjunction with Dr. DeBruin, Christina Riczu, Thomas Phan and Emilie Corcoran, we developed a compact, battery powered, 12-lead electro-cardiogram. The project won 1st place in the biomedical category at the ECE Capstone Poster Day.

Design and Implementation of a 12 Lead Portable ECG – [Link]

Haasoscope – Cheap, flexible, data acquisition for all!

Haasoscope is the first open-source, open-hardware, flexible, small, cheap, oscilloscope and data-acquisition board. You can use the stock firmware for basic oscilloscope functionality, or modify the firmware to customize what the Haasoscope does.

Preliminary features and specifications:

  • 4 x 100 MHz, 8-bit ADC channels with BNC cable inputs
  • Altera Max10 FPGA with 8k logic elements and 387kb of memory
  • Reprogram firmware over JTAG, or on the fly, with free Quartus II software
  • Readout over serial-to-USB at 1.5 Mb/s, about 20 Hz for 4 channels of 512 samples each
  • USB powered, (or other 5 V input, switchable), ~1.2 Watt
  • 8 x spare digital I/O
  • 9 x additional analog I/O with 1 MHz (1MSPS combined) at 12 bits
  • 7 x programmable LEDs, and a reset button

Haasoscope – Cheap, flexible, data acquisition for all! – [Link]

Arduino Weather Station using DHT11

Using a display to view the temperature and humidity of your environment can be possible using the DHT11 or DHT22 sensor with the easy to use Arduino microcontroller platform and that’s the goal of this project. For this project, we will be using the 16×2 LCD display module to display the temperature and humidity readings gathered from the environment using the DHT11 temperature and humidity sensor.

Arduino Weather Station using DHT11 – [Link]

Teardown, Repair & Analysis of an Agilent E4443A 3Hz – 6.7GHz PSA Series Spectrum Analyzer

In this episode Shahriar repairs an Agilent PSA Series Spectrum Analyzer. The instrument generates many errors during self-alignment and produces no measurements below 3.2GHz. The block diagram of the unit is thoroughly presented and various possible failure points are considered. Based on the observation of the noise floor, the most likely cause is the second LO module. The measurement of the LO power indicates that the second LO power is fall below nominal.

Teardown, Repair & Analysis of an Agilent E4443A 3Hz – 6.7GHz PSA Series Spectrum Analyzer – [Link]

Decoding and Encoding JSON with Arduino or ESP8266

In this blog post you’re going to learn how to decode (parse a JSON string) and encode (generate a JSON string) with the ArduinoJson library using the Arduino with the Ethernet shield. This guide also works with the ESP8266 and ESP32 Wi-Fi modules with small changes.

Decoding and Encoding JSON with Arduino or ESP8266 – [Link]