Posted on 08 Sep 2008
This project will be created for use with 2 LMD18200 H-Bridge ICs. These H-Bridges are capable of driving a motor with a voltage range of 10V-DC to 55V-DC with up to 3A continuous. It can drive the motor at a variable speed and reversible direction. It also has current sensing and thermal overload protection.DC motors can be controlled from the OOPic in a variety of ways utilizing everything from relays to power mosfets. This project shows how to configure two oPWMs and some oDIO1 Objects into a Virtual Circuit that will control the speed of two DC motors. with simple commands like M1Speed = 10 for a slow speed, M1Speed = 255 for full speed, and even M1Brakes = cvOn to slam on the brakes.[more]
Posted on 26 Aug 2008
The idea presented here uses the analog-to-digital converter (ADC) and pulse-width-modulation (PWM) hardware in the PIC16C72 processor to implement an efficient, low-cost, regulating power supply.The supply is intended to source less than 10 mA with minimal ripple but can source as much as 40 mA if more ripple can be tolerated. Ripple also can be decreased by increasing the inductor and capacitor values if size permits, and by modifying the software feedback control.[more]
Posted on 29 Jul 2008
This small project demonstrate the Tiny family high speed PWM capabilities to produce a sinewave output. It was also incorporated functions to play Piano Key Tones using sinewave waveform, as a smooth and clean sound as the ones produced by cords.
The sinewaves produces are better in low frequencies. The high frequency keys need to jump over a larger byte quantity in the sine table, to be able to produce the correct frequency, it generates a high frequency component over the sinewave, and it may be noticeable on the sound speaker.The circuit consists of ATTiny13 and RC low-pass filter. [more]
Posted on 03 Jul 2008
The schematics for this DC/DC converter is built around the UC3843 generic, low cost PWM controller. This very common PWM controller generate a duty-cycle modulated square wave ranging from 0 to 100%, at a user fixed frequency of 100KHz.Here are some features:
-Input voltage from 10V to 18V
-Output voltage from 20V to 28V adjustable
-Output current up to 5A for 3300mAh battery packs fast charge.
-Compact dimension (80×60mm)
-No heat sink or fan coolers even delivering up to 140W to the load.
[more]
Posted on 26 Jun 2008
The module consists of a Atmega8 microcontroller. It uses PWM to control 3 different LED’s found in a RGB Led. Because it uses PWM to control the 3 colours we can also control the brightness of the colours. This allows us to create various colours using the three original colors (Red,Green and Blue).[more]
