Well done, great job as always!

@sambenyaakov

4 жыл бұрын

Thanks. Welcome to join www.linkedin.com/groups/13606756

*Thank you sir, earlier I knew thermal simulation by only considering thermal resistance. And I always tried to find what should be the value of Thermal capacitance, needed for foster network design. Today it is a bit clear. Thanks sir* 😌😃

@sambenyaakov

3 жыл бұрын

Thanks for comment.

Very good presentation as usual, Sam !

@sambenyaakov

4 жыл бұрын

👍😊

Great explanation! Many Thanks!

@sambenyaakov

10 ай бұрын

Thanks

As always , BEST^n.

@sambenyaakov

4 жыл бұрын

Thanks😊

I have one question the provided value of Rthja in the datasheet ..does that represent worst case value? If it represents worst case value then is it only under the JEDEC recommended pad area and testing environment..it may be more or may be less as per the user pcb boards. Is my understanding correct?

@sambenyaakov

2 жыл бұрын

Look for the commnets and samll prints in data sheet for specification of copper area for which the Rth is quoted.

Sir, this is very good information.i have one doubt is that the thermal impedence for pulses is actually defining the PWM pulses.so, the same can be used for evaluating the temperature of a Mosfet while it's deployed for MOTOR CONTROLLER Application?

@sambenyaakov

4 жыл бұрын

Thanks for comment. Yes indeed. At low modulation frequency typical of motor drive this could be significant.

Mr. Sam, speaking of hestsinks and thermal resistances, how would we do in a situation where we want to use the PCB copper as heatsink for SMD devices. How can we calculate the thermal resistance or copper area in order to get certain temperature on the SMD device ?

@sambenyaakov

4 жыл бұрын

You need to do thermal simulation but most vendor s give the thermal hesitance of SMD when already on copper of certain area and some are giving for several different areas.

@catalin3407

4 жыл бұрын

Sam Ben-Yaakov Then, knowing the resistance for a given area, we can compute the new resistance for a new area knowing that the resistance is inversely proportional to the area, is this a way to go to avoid thermal simulation ?

Thank you for the video sir! I had one question about the thermal impedance curves. In all the graphs the pulse duration seems to be the only important variable for determining the thermal impedance, however the thermal conductivity of the material (lets say silicon) also changes with temperature. So should the thermal impedance not also be dependent on the temperature of the material? or is it negligible

@sambenyaakov

2 жыл бұрын

Good point. I don't know what is the temp effect on the thermal resistance. I would guess that it is minor.

cool i have 2 ac units i need too find away so to cant run at the same time like if some turn on one 2 cant run it cut the power off on one

@NiHaoMike64

4 жыл бұрын

Use a pair of relays. On each unit, wire it so that the thermostat signal goes through the NC contacts of the other unit. Then wire the coils so that it activates when its corresponding unit turns on. So turn on one and the relay disconnects the signal for the other one. Turn on the other one and nothing happens until the first one turns off.

@sambenyaakov

10 ай бұрын

Thanks.

Now translate to the temperature of the transistor junction.

@sambenyaakov

20 күн бұрын

Tj=Tcase+Ploss*Zjc

Hi! Nice video, but how do you calculate Rth1,2,3,4, Cth1,2,3,4?

@sambenyaakov

2 жыл бұрын

Which miniate in the video are you referring to?

@radioszurkefal2664

2 жыл бұрын

@@sambenyaakov at 7:00 when there are 5 RC blocks? How can I calculate the R C parameters?

@4:01 so after 0.1 second where curve is flat ( equilibrium) do we need to consider capacitor in the model if anyone want to analyse for longer pulse let's say 2 sec

@sambenyaakov

2 жыл бұрын

Indeed

What is "K" in the last slide?

@sambenyaakov

3 жыл бұрын

A scaling constant

@nachiketadeshmukh8444

2 жыл бұрын

@@sambenyaakov Thank you for your reply. How can we determine its value?

@sambenyaakov

2 жыл бұрын

/ @@nachiketadeshmukh8444 K is basically one but if large temperature drops are expected within the mass one can account for them by adjusting K. It can be estimated experimentally measuring the temp rise of a short thermal pulse so that the loss due to thermal conduction is still small