dsPIC MiniTron Amplifier

The MiniTron is a high end vacuum tube stereo amplifier with efficiency, distortion, and power output enhancements provided by some unique circuitry featuring a dsPIC30F2023 controller IC. The dsPIC is used in this project to create a tracking buck converter whose output voltage tracks the audio signal. The unique SMPS resources in these IC’s do most of the "hard stuff" usually required in an SMPS design, leaving ample processing power available for other activities.

These IC’s and the Avago galvanic isolators are truly the "enabling technology" for this project. The controller IC is also used to perform system health checks, and set the operating points of the individual vacuum tubes. This allows total system programmability, offering several possible preset operating modes.

© George Anderson

Download
Project Documentation

tag : Tube Stereo Amplifier, Audio, dsPIC projec

PIC based Animation Tile Display

Puzzlemation is an expandable platform of light and animation based on PIC24FJ64GA002. It can be used to create things as diverse as modular animated signs that can be changed by rearranging its tiles, to a uniquely animated puzzle. This project’s display is made of a number of tiles, about 2 inch square with an 8 x 8 array of color LED pixels. Each tile is individually powered and animated, so user can freely pick them up and re-arrange them. To set up a display, the tiles are placed in a special tray. Animations are downloaded into the tray via Ethernet and stored locally on an EEPROM, or loaded via an SD card. The tray broadcasts the animation to each of the tiles, and then synchronizes them.

John Peterson, project designer, said that the display is completely reconfigurable. If the pieces are left in the tray, the animation can be updated continuously over the Ethernet connection. If the tiles are removed from the tray, they’ll display the animation for several hours with their own re-chargeable battery power. Once the animation is synchronized and running on the tiles, user can pick them up and place them anywhere.

Download:
Project Documentation, Source Code and Schematic(zip)

tag : Display, LED, project, PIC, PIC24FJ64GA002, animation, puzzle

PIC Based GPS to SD-Card Data Logger

This project combines a GPS receiver module, a Microchip PIC microcontroller and a Secure Digital memory card to make a GPS data logger. With a large capacity and reasonably long battery life it is a very useful device for logging GPS position for example for mapping with OpenStreetMap.

The data from the GPS is logged every second with the raw NMEA sentences being written to the SD card. The data written to the card is the GSA, GGA, RMC and GSV sentences which by excluding the carriage returns this should never exceed 512 bytes per second. The data contains:

• GGA - 78 bytes - time, fix, lat, long, altitude, horizontal dilution of precision.
• GSA - 69 bytes - fix (none, 2D, 3D), satellites used, dilution of precision.
• RMC - 78 bytes - time, lat, long, speed, course, date.
• GSV - 74 bytes - satellite information (4 messages).

The total active power consumption is about 40mA to 45mA when active which in theory should give 48 hours on rechargeable batteries with 2000mAh capacity. In practice I have measured a time of 40 hours.

Download : schematic and source code
related serch : Microcontroller Circuit Project, GPS, SD Card, Data Logger, PIC (src)