YAY... my first thred... LOL sorry... I just bought a Logitech Wheel Mouse Optical (using USB port)and plugged it in.. played c-strike for less than a minute.. and decied I liked my new mouse and that I would keep it. I then took it apart Everything fell out when I ripped out the pcb(well, ok... I was gentle with it...) but I got it all back together alright Well, now for the mod... I want to add a capacitor between the leads of the LED to make a fade effect of about 1 to 4 seconds when the mouse goes into a power saving state (I think that's what it does). Anyways, the led goes dark rather quickly after no movement, and thought that a fade effect would be cool. The voltage I can find myself, with me multimeter. Shall post voltage once I take the mouse apart again, in case any one is interested... well.. the voltage when the LED is on full power is 2.17 Volts and when in standbye like mode it is 0.19 Volts And am currently using with the cover off...
lol.. I think I gonna need a bigger capacitor than what I got... I just tried a 1000uF electrolitic rated at 25V and no go.. even on a normal green LED, the fade was a bit longer than wanted... So I may require some circuitry to fade it between the two... sniff.. so much for a simple mod that takes less that 30 seconds to do... know of any ways to fade do that? Don't worry.. all is not lost.. if I have to, I will make my own circuit to do that
You can choose a smaller cap, or you can use a transistor (And put the cap on the base of the transistor)
Thanks Shall try that now with the green led... post again in maybe an hour or so, or sooner if I get it working/burn something out... LOL ok.. I got a test to work... I forgot that the led would have a current limiting resistor between it and vdd... LOL so... my test circuit looks like: Code: vdd | |---------+ cap resistor | | | LED |---------+ | Gnd and the fade works great with the 1000uF cap... BUT... I must find out the current draw of the led.. so I shall hack apart the mouse a bit... LOL and then maybe get the circuit into place after I find out the current draw and find out which led lead has the voltage change on it and use that as either ground or vdd, and change the circuit accordingly... Thanks for your help ZAP... made me get out my bread board... ok.. well... I did have to use a transistor.. and almost burnt one out... hooked it up wrong and wondered why it never worked. So I tried checking to see if it was hot and burned my finger.. but I tested it with the mouse and works fine... shall post a schematic and piccies of what I did later tomorrow sometime... and hopefully a vid of the fade effect Now all I gotta do is cut the wires to the led... Well... got it all wired up and a pcb all soldered up. Then I put it in me mouse... Looks great... But theirs only one thing...One of my friends that has the same mouse hates me now(well, hes actually jealous but whatever) I shall add piccies and maybe an animated gif. And maybe I shall do up the schematic on my computer since my writing is really messy.
I merged all your posts. 3 posts in a row is generally not a good idea. Use the "Edit" button not the "Post Reply" button if your post was the last one - :: Phat ::
Thanks for advice Phat... never thought of that ok.. I got a schemtaic all done up.. and hope to get some piccies of the circuit in action. I also changed the red led for a green one the schematic done in eagle yes yes.. R1 is about half what it should be... but I wanted the green led to be a bit brighter, and is not at the maximum rating of the led. The vdd wire connects to the red wire coming in from the mouse which is about plus 5 volts. Ground is either of the two black wires. Any comments would be nice, thanks EDIT: ok.. here is a crummy animated gif of the mouse... and my fingers note: effect looks WAY cooler in real life, and led is looks brighter... In fact, how bright it looks when is on full power in pick is about what it looks like when in power saving mode. Anyone want pics of the connections on the pcb??? Don't worry, I soldered most of everything... , except vdd and gnd Questions, comments.
That means the transistor is connected the wrong way round as shown. And as ZapWizard said, small caps can be used between transistor base and ground instead of big ones across the led.
