2.5V to 36V, 2.5MHz, PWM Boost Controller with 4μA Shutdown Current

by Graham Prophet @ eedesignnewseurope.com:

Maxim Integrated has posted details of the MAX17290/MAX17292 high-efficiency, synchronous step-up DC-DC controllers, that operate over a 4.5V to 36V input voltage range with 42V input transient protection and feature reduced EMI. The input operating range can be extended to as low as 2.5V in bootstrapped mode.

2.5V to 36V, 2.5MHz, PWM Boost Controller with 4μA Shutdown Current – [Link]

How to Make Your Own ARDUINO UNO Board

Being Engineers @ instructables.com writes:

Hello guyz, Welcome to Being Engineers. Hope you all are doing good. In this tutorial we will learn how to make your own Arduino Uno. We will gather the components, test the circuit in breadboard, then we will make the board itself. When it is done we will know how to program the Arduino IC AKA Atmega328p on board.

How to Make Your Own ARDUINO UNO Board – [Link]

DIY Arduino Soldering Station

GreatScottLab @ instructables.com writes:

In this project I will show you how to create an Arduino based soldering station for a standard JBC soldering iron. During the build I will talk about thermocouples, AC power control and zero point detection. Let’s get started!

DIY Arduino Soldering Station – [Link]

BQ25504 Solar Cell LiPo Charger

by Pesky Products @ tindie.com:

This is a small (0.5 x 0.5 inch) breakout board for Texas Instrument’s BQ25504 Ultra Low Power Boost Converter with Battery Management for Energy Harvesting Applications.

BQ25504 Solar Cell LiPo Charger – [Link]


Reliable molecular switch

by Eric Bogers @ elektormagazine.com:

Nanotechnology repeatedly breaks new records in the area of miniaturization. However, there are physical limits when reducing the size of electronic components and these will be reached in the near future. This means that new materials and components will be required – and it is here where molecular electronics will play a role. Researchers from the Karlsruher Institut für Technologie (KIT) have succeeded in developing a molecular toggle switch, which will not only remain in the selected position, but can also be switched as often as desired without any deformation taking place.

Reliable molecular switch – [Link]

Simple Pressure Sensor Amplifier & Over Pressure Switch

The pressure sensor amplifier built using LM358 op-amp and MPXM2051GS pressure sensor from NXP semiconductor.  The circuit provides 4V output for full scale pressure input 0-7.5PSI.  One op-amp is used as amplifier and 2nd op-amp is used as comparator to provide an output at set value that can be used as over pressure switch to control a pump or solenoid.  This is a low cost general-purpose circuit for those applications where +/-3% performance is acceptable. Multi turn potentiometers are provided for Offset, span adjust & over/under Pressure set point to control output devices like solid state relay, Pump, and solenoid.


  • Supply 12V DC
  • Pressure Sensor range 0-7.5PSI
  • Output 0-4V (Approx.)
  • PR1 Multi-Turn Potentiometer Offset
  • PR2 Multi-Turn Potentiometer Span Set
  • PR3 Multi-Turn Potentiometer Comparator (Switch) output Set
  • D1 Power LED
  • CN1 4 Header Connector Outputs & Supply Input

Simple Pressure Sensor Amplifier & Over Pressure Switch – [Link]

50 Segment Serial Bar-Graph Display Driver

The serial controlled 50 Segment Bar-Graph Display built using CAT4016 IC. Very useful projects for development Bar-Graph based, Temperature Meter, Interactive Games, Voltage Display, Current Display., Pressure Sensor, Magnetic field meter and PH Meter. Tilt meter, LUX meter.

The CAT4016 is a 16 channel constant current driver for LED billboard and other general display applications. LED channel currents are programmed together via an external RSET resistor. Low output voltage operation on the LED channels as low as 0.4 V (for 2 to 100 mA LED current) allows for more power efficient designs. A high−speed 4−wire serial interface of up to 25 MHz clock frequency controls each individual channel using a shift register and latch configuration.

50 Segment Serial Bar-Graph Display Driver – [Link]

3.3V @ 1.5A Buck Regulator

The circuit presented here is based on LTC3601, a high efficiency, monolithic synchronous buck regulator from Linear Technology. The circuit operates at an input voltage ranging from 4V to 15V, this makes it suitable for a wide range of power supply applications. It is capable of producing a output voltage of 3.3V. Burst Mode operation and forced continuous mode are the two types of operational modes available in LTC3601.


  • Input(V): 4VDC to 15VDC
  • Output(V): 3.3VDC
  • Output load: 1.5A
  • PCB:35mm X 25mm

3.3V @ 1.5A Buck Regulator – [Link]

Creating a Smart Water Sensor with the ESP32 Thing

Alex the Giant @ sparkfun.com has a tutorial on how to build smart and connected water sensor using ESP32. He writes:

For this project, you can use either the ESP8266 Thing, or the ESP32 Thing. One of the many improvements made on the ESP32 is the capacitive touch circuitry built in to ten of the IO pins (we can see the pins capable of capacitive touch in the datasheet below). It should be noted though, that Touch1 cannot be used as capacitive touch sensor because of the pull-up resistor connected to GPIO pin 0. With the capacitive touch, we’ll be able to sense water with just two pins; the first will be connected directly to a capacitive touch pin, and the second will be connected to ground.

Creating a Smart Water Sensor with the ESP32 Thing – [Link]