High Current Discrete Half-Bridge Based on IR2104 or IR2101


This is a discrete Half-bridge driver based on IR2104 gate driver IC and low impedance high current N channel IRFP4368 MOSFETS. The IR2104 is a high voltage, high speed power MOSFET driver with independent high and low side referenced output channels. HVIC and latch immune CMOS technologies enable ruggedized monolithic construction. The logic input is compatible with standard COMOS or LSTTL output, down to 3.3V logic. A gate IR2104 driver is a power amplifier that accepts a low-power input from a controller IC and produces a high-current drive input for the gate of a high-power transistor such as a power MOSFET. In essence, a gate driver consists of a level shifter in combination with an amplifier.

This drive has many application, ranging from DC-DC power supply for high power density and efficiency, This project simplifies the design of control systems for a wide range of motor applications such as home appliances, industrial drives, DC brushed motors , Brushless motors, fans, Tesla Coil driver, Induction coil driver, LED driver, Halogen Lamp driver.

High Current Discrete Half-Bridge Based on IR2104 or IR2101 – [Link]

Dynamic-load circuit determines a battery’s internal resistance


by @ end.com

The simplest model of a battery comprises an ideal voltage source that connects in series with a resistance whose value—often a few milliohms—depends on the battery’s electrochemical condition and construction. If you attempt to use an ordinary ac milliohmmeter containing a kilohertz-range ac excitation source to measure a battery’s internal resistance, you get erroneous results due to capacitive effects, which introduce losses. A more realistic battery model includes a resistive divider that a capacitor partially shunts (Figure 1). In addition, a battery’s no-load internal resistances may differ significantly from their values under a full load. Thus, for greatest accuracy, you must measure internal resistance under full load at or near dc.

Dynamic-load circuit determines a battery’s internal resistance – [Link]

16 Channel InfraRed remote controller


16 Channel Infra-Red remote controller is based on PIC16F73 Microcontroller from Microchip. The receiver part follows RC5 (Philips) Code Format. Tiny receiver provides 16 latch outputs or 8 Latch + 8 Momentary outputs by closing Jumper J1. All outputs are TTL and can drive Relay board or solid state relay. The circuit uses TSOP1738 Infra-Red receiver module which provides high degree of noise immunity against interfering light source.


  • Supply Remote Transmitter RC5 Philips 2XAAA Battery
  • Supply Receiver 7V to 12V DC
  • Modulation 38Khz
  • Philips RC5 Code Format
  • Operating range up to 20 feet
  • 2 Pin Screw Terminals for Supply Input
  • On Board Power LED
  • Onboard VT (Valid Transmission) LED
  • All Outputs TTL Level provided with Header Connector
  • Jumper (J1) for Mode Selection
  • J1 Open 16 Latch Outputs
  • J1 Closed 8Latch + 8 Momentary

16 Channel InfraRed remote controller – [Link]

Consolite – a Tiny Game Console on an FPGA


Robert Fotino has design a video game system on a FPGA. He writes:

For my latest project, I am diving back into Verilog to create the hardware side of Consolite. For those who don’t know, Consolite is the name I’ve given to my design of a tiny hobbyist game console and associated software toolchain. In my previous posts, I demoed a compiler that translates from a flavor of C to Consolite Assembly, an assembler that translates from Consolite Assembly to binary files, and an emulator that runs the resulting binaries.

Consolite – a Tiny Game Console on an FPGA – [Link]

Butchered USB TTL Serial Adaptor


Aaron Brady writes:

We popped open the case, and there were two main ICs, a Prolific 2303 (the USB to Serial IC) and a ADM3251E (the RS232 line level convertor). I tried to desolder this with no success, but Bas stepped in, cut the leads with a craft knife and ran the iron over the chip’s leads and it basically fell off. He also did the very fine soldering to pins 1 and 5 of the Prolific chip, TX and RX respectively.

Butchered USB TTL Serial Adaptor – [Link]

Learn how to play sound with Arduino by building a DIY Micro Piano

In this video we are going to learn how to make sound with Arduino. We are going to build a simple Micro Piano in order to demonstrate the capabilities of the tone function. Let’s start!

Playing back sound is great for adding audio feedback to our projects. So far we were using displays or LEDs in order to provide feedback to the user of the project. Today we will learn how to make sound with Arduino and as you are going to find out, it is very easy.

In order to demonstrate the sound capabilities of the Arduino Uno, I have built a simple project, a micro Piano. Each time I press a button, Arduino makes a sound of a specific frequency for each button. The frequencies correspond to specific music notes, we have 7 buttons, so we can have 7 notes! So, let’s try it. I am going to play a simple song using the available notes.

Learn how to play sound with Arduino by building a DIY Micro Piano – [Link]


WiFiRGB – A WiFi-enabled RGB high-power LED


Tom blogged about his WiFi/Browser controlled RGB LED project:


Simple hardware, using pre-fabricated modules

Controls an RGB LED via any recent browser, any operating system

WiFi credentials can be configured via browser

Software is written as an Arduino sketch

WiFiRGB – A WiFi-enabled RGB high-power LED – [Link]



samDEV_09 – Mini devboard for Atmel’s SAMD09 ARM Cortex M0+ Microcontroller


A Basic board to test the Atmel SAMD09. On board there is also a CH340 uart to usb bridge

Build this board to getting started with the SAMD microcontroller family after I made the mistake to try the much bigger SAMD21 first. The SAMD09 used here is he smallest from this family and therefore has the shortest (still 709 p.) datasheet. I think this board will be, as my other microcontroller breakout boards, very useful for an early prototyping phase on breadboard. So far I quite like the SAMD09. If you compare it to the the ATmegas there are a lot more possibilities. Maybe this is the Arduino Nano killer for me.

samDEV_09 – Mini devboard for Atmel’s SAMD09 ARM Cortex M0+ Microcontroller – [Link]

Simple nanosecond-width pulse generator provides high performance


by Jim Williams @ edn.com

If you need to produce extremely fast pulses in response to an input and trigger, such as for sampling applications, the predictably programmable short-time-interval generator has broad uses. The circuit of Figure 1, built around a quad high-speed comparator and a high-speed gate, has settable 0- to 10 ns output width with 520 ps, 5V transitions. Pulse width varies less than 100 ps with 5V supply variations of 65%. The minimum input-trigger width is 30 ns, and input-output delay is 18 ns.

Simple nanosecond-width pulse generator provides high performance – [Link]

Micro-supercapacitor fits inside IoT chips


by Jan Buiting @ elektormagazine.com:

Zero-power autonomous devices will abound on the IoT of the future, and battery manufacturers are scratching their heads to come up with the best possible solution ensuring high energy and power density at miniature scale. A new material developed recently at Finland-based VTT shows promise, based on energy and power density of a supercapacitor depending on the surface area and conductivity of the solid electrodes. The size? So small it fits inside an IC.

Micro-supercapacitor fits inside IoT chips – [Link]