Posted on Wednesday, 14th October 2009 by Auw Jimmy
I have made RGN/B4/B5 to Octal Converter few weeks ago. Actually, the converter was made for 1A RGN Rectifier (because of the resistor drop value). I put 2 x 0.5 Ohm to drop 1V from 5V to 4V. With 1V voltage drop and around 1A current, I expect around 1W power dissipation. So this 6.5W Dale resistor should be fine (although a little bit warm after several hours of usage).
Later, I decided to make a new converter for 2A RGN Rectifier. Assuming 2A current and 1V voltage drop, the 5W or 6.5W Dale resistor should be fine, right? Wrong!!! My 5W Dale resistor got overheated (completely untouchable by hand) around 30 minutes of operational time.
Was I losing my math? I didn’t know.
So, I made another converter consisting two resistor in parallel. So the total power dissipation should be around 13W (2 x 6.5W). We’ll see whether those will get overheated again or not