Spacewrench over at Dorkbotpdx published a new build, a Power Playground project:
It’s a PMOS/NMOS H-Bridge with FETs that can handle 3 amps or so, plus a SPI current sensor, some switches & a rotary encoder (not stuffed yet), and a 7-segment display, all controlled by a Teensy-3.1 running FreeRTOS.
I made this because I’m always running into battery, power, inductor and transformer issues I don’t have any experience with. The idea is to use the H-bridge configuration and current sensors to experiment with moderate-current PWM, motor control, power-line synchronization, battery charging and discharging, etc.
Power playground project - [Link]
This evaluation board has been developed for ROHM’s H-Bridge driver customers evaluating the BD62x2FP series. The BD62x2FP series can operate across a wide range of power supply voltages (from 3V to 32V max), supporting output currents of up to 2A. PWM signal control (20 kHz-100 kHz) or VREF control modes are used to vary motor rotation speeds. ROHM’s ICs are complete with over current protection (OCP), over voltage protection (OVP), thermal shutdown (TSD) and under voltage lock-out (UVLO) protection circuits while also facilitating a low-power consumption design (10μA max).
Rohm H-Bridge Evaluation Board - [Link]
H-Bridge Motor Speed Controller Tutorial - [Link]
If you have an H-Bridge drive circuit for a motor, you may need a way to monitor the load on the circuit. This circuit is nice because it provides a single output that could be monitored with a microcontroller or other device. The trick is to use current sense amplifiers and measure the current on each leg of the circuit. The LTC6103 is a good choice because it has two sense amplifiers in the same package.
Here is a circuit diagram that will allow you to monitor the load.
Monitor your H-Bridge Circuit Load - [Link]
[MAXIM APP 5509] This document details the Oceanside (MAXREFDES9#) subsystem reference design, a 3.3V to 15V input, ±15V (±12V) output, isolated power supply. The Oceanside design includes a high-efficiency step-up controller, a 36V H-bridge transformer driver for isolated supplies, a wide input range, and adjustable output low-dropout linear regulator (LDO). Test results and hardware files are included.
Isolated power is required in many applications such as industrial and medical applications. The Oceanside design uses a step-up controller (MAX668), a 36V H-bridge transformer driver (MAX13256), and a pair of LDOs (MAX1659 x2) to create a ±15V (±12V) output isolated power supply from a wide range of input voltages. This general purpose power solution can be used in many different types of isolated power applications, but is mainly targeted for industrial sensors, industrial automation, process control, and medical applications.
3.3V to 15V Input, ±15V (±12V) Output, Isolated Power Supply - [Link]
Chris from PyroElectro has posted his plans for a 10-A H-Bridge motor controller that avoids using the the typical controller ICs. He writes:
Motor control is the core heart of robotics. Without locomotion or any movement a robot is dull and lifeless. The H-bridge is a tried and true concept for DC motor control. It allows you to move motors forward, backward and with varying speeds through PWM (pulse with modulation).
This tutorial will take a few steps back from the all-in-one L298 or LMD18245 motor control ICs and look more into how we can build our own H-bridge without the need of an IC.
10-A H-Bridge motor controller - [Link]
This year I wanted to try something a little different then my usual mash-up costumes. I decided to go big or go home and what better way to make something big then to inflate it. So this year I am going to convert a 8’.5” foot tall 7’ wide Stay Puft Marshmallow Man Inflatable Lawn Decoration into a portable / wearable costume.
The first step I would need to do is check to see if the fan motor will work on a portable DC power source. I was a little bit saddened when I read the sticker on the power supply. It read output voltage 12vac. If it was a synchronous motor the whole project would be canned but it turns out that when I hooked up a 12vdc power source the fan turned on and worked as it normally would. So I am guessing that either the label was printed incorrectly or the LED’s inside some how were part of an H-bridge to convert AC to DC.
Wearable Inflatable Lawn Decoration Costume - [Link]
One of the advantages using the Microchip PIC microcontroller Pulse Width Modulation or PWM for short is; this PWM peripheral circuit is designed to control the DC motor using the full bridge mode PWM feature. The PWM peripheral works by supplying the correct signal to the H-Bridge DC motor circuit such as speed controlling and changing the DC motor direction. Therefore on this tutorial we will learn to use this sophisticated feature offered by Microchip PIC PWM. For those with the AVR microcontroller background this is also a good chance to learn the beauty of the different between AVR and PIC microcontroller especially in the PWM peripheral features.
H-Bridge Microchip PIC Microcontroller PWM Motor Controller – [Link]
rsdio tipped us to an app note on isolated power-supply circuits: [via]
Wow! It’s quite interesting to see how to substitute capacitors for a transformer. Without digging deeper, though, it’s not clear whether voltage boost can be achieved.
An integrated H-bridge driver for isolated power-supply circuits (MAX256) usually drives the primary of a transformer, but it can also drive a pair of capacitors that substitute for the transformer in providing isolation and power transfer.
Isolated power using capacitors – [Link]
Here is a very simple project of controlling a small DC-motor (taken from an old personal cassette player) with ATmega8. The ATmega8 is having three PWM channels, out of which two are used here. PWM waveforms are fed to MOSFET (RFD3055) H-bridge. Here, direction is controlled using a two-position toggle switch and speed of the motor is controlled by two push-buttons, one for increasing the speed and other for reducing.
Simple PWM DC motor control using MOSFET H-Bridge with AVR ATmega8 – [Link]