I’d really appreciate it GREATLY if someone could suggest help or ideas for interfacing a Sanguino with a Velleman K8064 voltage-controlled dimmer kit: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1266079091
The K8064 appears to work best when controlled with a DC voltage from 1.5 to 10.0 volts, and I’d like to use all of that range, if possible. I’ve read the forums, the playground, and even other places, and have a decent idea of what I want to do, but generating the voltage range is getting beyond my meager skills.
can this chip be pwm 'ed or do you need real analog signal
if PWM: transistor or fet and 10V powersupply will take you a long way
Take a look at this thread: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1261144340
I was looking for between 0 - 12v but I don’t think 10v will make much diffrence. Think I used a TIP102 (or equiv) as I wasn’t certain how much current it would sink. In hindsight a 2N2222 would be fine.
First off, MANY THANKS for your replies. Since Massimo originally mentioned this Velleman dimmer a few years ago, I’m confident it should work with PWM and an RC filter. It was after reading the Velleman forums I found the working voltage range to be a problem. GrumpyMike’s suggestion to “wire up one of the Arduino’s PWM outputs to a transistor, with a 1K base resistor and 4K7 collector resistor. This gives you a 12V PWM.” sounds ridiculously simple.
So the Arduino’s PWM pin connects to the transistor’s emitter, but where does the base+1K resistor connect, and the collector+4K7 resistor connect? I presume it’s to ground and +12V, but which goes where? :-/ (I’m a software guy, not an EE.)
Thanks for helping!!
Remember to add the collector resistor.
but where does the base+1K resistor connect,
To the PWM output pin of the arduino.
and the collector+4K7 resistor connect?
The other end of the 4k& goes to the +12V. With emitter to ground.
for transistors driving external loads and :-
for a discussion on PWM.