How servo motors work and how to control servos using Arduino

Dejan Nedelkovski over at HowToMechatronics shared detailed tutorial on how servo motors work and how to control servos using Arduino and PCA9685 PWM driver: There are many types of servo motors and their main feature is the ability to precisely control the position of their shaft. A servo motor is a closed-loop system that uses […]

App note: Fan speed control is cool!

App note from Maxim Integrated about their MAX6650 and MAX6651 fan controllers chip. Link here (PDF) Temperature-based fan control is a necessity in a growing number of systems, both to reduce system noise and to improve fan reliability. When fan control is augmented by fan-speed monitoring, a speed-control loop can be implemented that is independent […]

4-20 mA current output for Arduino Uno

Giovanni Carrera writes, “The purpose of this project is to provide a 4-20 mA output from a PWM signal generated by a microcontroller ATmega328 and numerous other chips, such as the PIC. One of the more interesting applications of this circuit would be to replace or to realize a smart sensor with Arduino.” More details […]

An isolated analog output for Arduino Uno

Giovanni Carrera writes: This project completes the series of my articles about the Arduino analog I/O with the aim to use it as a controller of small automation systems. In control systems of the industrial plants it is always advisable to isolate both the inputs and the outputs coming from the field. This prevents disturbances […]

App note: LED back light driving methods

Using pulse width modulation scheme for LCD back lighting an app note from Hantronix. Link here (PDF) LED back lights on LCD modules are generally driven with a dc voltage through a current limiting resistor. This simple approach is perfectly acceptable for most applications. When the primary consideration is an extra bright display, the lowest […]

DIY PWM to PPM converter for 2.4GHz receiver using Arduino

A DIY PWM to PPM converter using an Arduino Pro Mini from Al Prettybong.  Oscar wrote a post on his blog detailing how Al made it: For radio receiver, there are a few output signal formats. The traditional and also most common type of RX signal is the PWM and basically PWM requires 1 cable […]

App note: Accurate, fast settling analog voltages from digital PWM signals

Accurate, fast settling analog voltages from digital PWM signals, app note from Linear Technology (PDF!): Pulse width modulation (PWM) is a common technique for generating analog voltages from a digital device such  as a microcontroller or FPGA. Most microcontrollers have dedicated PWM generation peripherals built in, and  it only takes a few lines of RTL […]

UC3844 base motor speed controller

Dilshan Jayakody writes: UC3844 is popular current mode controller which is commonly found on DC-to-DC converter circuits and switch mode power supplies. This motor speed controller is also based on UC3844 and it is specifically design to drive 20V – 24V DC motors. In this given configuration UC3844 produces (approx.) 50kHz to 240kHz PWM output […]

App note: High-Precision 16-Bit PWM

Technical brief from Microchip on their high-precision 16-Bit PWM modules found on various PIC16 devices. PDF link here The high-precision 16-bit PWM available in various PIC16 devices such as the PIC16F1574, delivers advanced features beyond those found on standard PWM modules. These innovative features allow the user to easily vary phase, duty cycle and offset […]