Some diagrams illustrating how to use the tip120 transistor to control 12 v (actually up to 60v dc)
12 v lamp:
DC motor (only difference is the diode connected between collector and emitter.
A detailed diagram for the tip 120:
A simple example code for on/off using max/msp and arduino from Tom Igoe´s pages works fine to test the transistor as a switch.
Another example combining max/msp and arduino to fade a lamp for instance.
February 14, 2008 at 10:25 pm
[...] examples + tutorials: tip120 transistor: controlling dc motors and lamps from thearduino « Connect the Dots Physical Computing at ITP | Tutorials / High Current [...]
December 3, 2009 at 1:00 am
[...] blog “Connect The Dots” gave me the schematics, but I did not want to use a TIP120 I do not have, i googled again the [...]
August 2, 2010 at 6:23 pm
[...] higher than 5v, using the data from the CT Sensor. In order to do this I would need to use a transistor because the Arduino can only be used to power an appliance between 0-5v. When doing this I had to [...]
August 2, 2010 at 6:23 pm
[...] higher than 5v, using the data from the CT Sensor. In order to do this I would need to use a transistor because the Arduino can only be used to power an appliance between 0-5v. When doing this I had to [...]
August 11, 2011 at 9:29 pm
ref: http://www.imagesco.com/articles/picstepper/03.html & http://www.produktinfo.conrad.com/datenblaetter/150000-174999/150872-da-01-en-Transistor_TIP_120.pdf
The tip 120 transistor has a built in protection diode and I believe it thus does not require an extra one such as in your second diagram… I’m no electronician and if I’m wrong, I would love to understand why !
Regards
August 11, 2011 at 9:30 pm
http://www.learn-c.com/tip120.pdf
March 26, 2012 at 11:09 am
FYI: External fast diode is required if load is inductive (motors, switching inductor power supplies, etc)
Internal diode is die substrate & non optimum so vulnerable to fail shorted from repetitive turn off inductive kick back EMF and is not as fast a recovery time as desired to optimize transistor recovery.
An Nchl Logic Level Power FET is a better choice for many reasons
no constant base power as with fwd biased junction, (FET gate is a capacitor), devices easily paralleled for higher load currents, DS still needs protected against kick back EMF
Dale, So Calif, K3MNN, FIRST, TRW
March 26, 2012 at 12:46 pm
Thank you for the explanation !
March 29, 2012 at 8:56 pm
you are welcome.
If you live in LA SoCal area
TRW Swapmeet is this Sat 7am-noon corner Aviation & Manhattan Beach Blvd just past Marine Ave (about mile so 405 Rosecrans off ramp)
Lots of surplus electronics for sale & people to talk tech with
Ham Radio Electronics galore.. I’ll be there if not too pooped out after Judging LA County Science Fair at Pasadena Convention Center 7am – 9pm Fri
Dale (DaleScience@aol.com I live in W.Torrance)
March 29, 2012 at 11:29 pm
It’d be an achievement to meet you there, I’m in Germany at the moment
I would have loved going to such an event though…