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Thermal Time Constant ?
This app note states: Quote:In general, transient thermal effects die out in most power transistors within 0.1 to 1.0 seconds. This time depends on the material and construction...
Saturday, 5 November 2011 - 14:33
Thermal Time Constant ?
The average is only relevant if the cycle doesn't take too long. Cause I could dissipate 100w for example for 3 minutes in a TO-220 and than have it idle at 0w for a year, the...
Saturday, 5 November 2011 - 13:20
Thermal Time Constant ?
david.prentice wrote: Regarding the thermal time constant, you generally design for the steady state average power dissipation. Very high peak dissipation will give you some...
Saturday, 5 November 2011 - 12:33
Thermal Time Constant ?
Seriously I think I'm going blind. I didn't even see there was a general electronics forum.
Saturday, 5 November 2011 - 10:42
Thermal Time Constant ?
bobgardner wrote:If you can touch it, it aint too hot. That's one way to go about it. But I was looking for numbers.
Saturday, 5 November 2011 - 00:29
Help -Spliting a project into multiple files.
:oops: Thanks guys.
Sunday, 30 October 2011 - 21:09
Bitbang USB solution: V-USB vs AVR309 [app notes]
By "here" i mean in Israel. I could order components from digikey/farnell or whatever, thing is the delivery costs about 50$. So I can't do that for prototyping. Besides I don't...
Wednesday, 19 October 2011 - 17:29
Bitbang USB solution: V-USB vs AVR309 [app notes]
USB models cost a fortune here, the only available usb mcu i can get would be a pic and it is still very expensive. I didn't really did my homework about USB protocol... Can't I...
Tuesday, 18 October 2011 - 21:37
Making a simple IR detector using an IR photo diode.
Ok, this might be silly. Is there any chance that the "photo diode" I have is actually an LED ? Did anyone come across an IR led with a dark blue lense ? I just connected it to a...
Monday, 17 October 2011 - 21:03
Pulsed current though a led help me understand the datasheet
Let's try it, here is a random IR led datasheet. Continues current max power dissipation P=If*Vf P=100mA*1.5 = 150mW [Vf taken from I/V curve] It also matches to the max power...
Monday, 17 October 2011 - 21:01
Making a simple IR detector using an IR photo diode.
I can't really tell what type of diodes these are. The IR LED look almost like a regular clear LED with a light blue tint. (I can take a photo if that's helpful) The photo diode...
Thursday, 13 October 2011 - 19:38
Making a simple IR detector using an IR photo diode.
I tried building this: But the voltage on the resistor didn't change when I turned the IR light off.
Thursday, 13 October 2011 - 18:24