I have seen some web pages defining that current sinking and current sourcing are same. But the truth is that they are different. This is a tutorial about current sinking and current sourcing in Integrated Circuits(IC).
Author Archive for admin
More example programs for Octave has been posted in my wiki page. Please vist
If you don’t know about Octave, I have been maintaining a wiki page for Octave. See the link below
http://jeffrey.co.in/wiki/doku.php/experiments_using_octave_for_b-tech_course
This time I am with an AVR USB board. It is an tiny development board for the AT90USB162 chips. I have actually made this board design for my friend’s main project. The design has been made using gEDA. It’s an complete open hardware project. But still the schematics are missing.
Actually I have started drawing the board layout using pcb directly instead of using gsch2pcb. I will try to upload the schematic of the board soon as possible.
Special thanks to Sreeraj and Pramode Sir. This project was completed 3 months before. But I didn’t have much time for blogging. Sorry for the late post.
Here are some of the reference links
ATMEL AVR USB AT90USB162 MICROCONTROLLER PROTOTYPE DEVELOPMENT BOARD
AVRopendousDIP - avropendous - Open Hardware Development Board for the AT90USB162
Here is the board layout file.
sree-usb-noicsp.pcb
Here are some snapshots.
Last day I bought a USB MP3 player board from a local store in Thrissur. This board can read MP3 files from a USB thumb drive and play it for you.
The board circuit diagram is so simple that there are a very few connections. some of the connections are
- IR sensor connection (3 wires - IR data, VCC, GND)
- USB socket connection (4 wires - VCC, D-, D+, GND)
- Power supply 5V (2 wires - VCC, GND)
- Audio Out (3 wires - Left, Right, GND)
- Switch (4 wires - Next, Previous, Play, Mode)
The other main features are an built in FM receiver and also an remote control. The player can read up to 1999 songs. I have not tried any other music formats other than MP3.
The main attraction is its cost. The board cost only 250 Rupees ( 5$).
If anyone needs the connection diagram of the board please do contact me 
Here are some screen shots
Note(Nov 28, 2009): This is not an open hardware project. Please don’t ask for circuit diagram. I actually bought this circuit board from a local store. The connection details are so easy. The board has markings on it for the connections.
Two days before I got my CPLD (complex programmable logic device). Here are some snap shots of my CPLD XC9536.
The main problem is that there is not much support for programming these CPLD xc9536 using free software. There are tools available for programming this cpld. But all of them are for Windows platform.
But there is a small hope. The xilinx website is giving a software named ISE WebPACK Design Software. It’s linux version us available for download.
I have to start hacking the CPLD soon. I have designed the PCB for the JTAG Parallel Cable programmer using PCB.
I would like to say special thanks to Omkar Kulkarni for helping me a lot. He has written a very good tutorial for programming this xc9536 CPlD. check this link http://elecrom.wordpress.com/2008/03/02/getting-started-with-xilinx-xc9536/
Here are some links that might be useful.
