Recent content by SwedishWings

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    Understanding transistor Ptot in data sheet

    What does "Derate above 25°C - 5.0 mW/°C" actually mean? Is it the SOA that falls with 5mW/C?
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    Understanding transistor Ptot in data sheet

    Thanks for clarifying, think i understand now. But does the Tc based Ptot refer to _zero_ thermal resistance to 25C? That would be purely theoretical, right? Great idea, never thought about it =)
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    Understanding transistor Ptot in data sheet

    I totally missed the fact that there are heat-sinks for those casings. Thanks!
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    Understanding transistor Ptot in data sheet

    Yeah, i think i might have mixed up the data sheets, that would be the TO-18 case. But are there any heat-sinks for TO-18?
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    Understanding transistor Ptot in data sheet

    Hi, Reffering to the attached image, I wonder how total power dissipation is defined in each case; "Tamb < 25C" and "Tc < 25C" respectively. I suspect that Tc is referring to usage with a heat-sink , but it makes no sense as the TO92 case is not well suited for heat sinks. Thanks in advance!
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    R/C Plane Simulation Software - Tips & Advice Wanted

    Thanks a lot! I have started reading and find it quite easy to follow, though some explanations would help. I stumbled on some very simple equations on this http://www.grc.nasa.gov/WWW/K-12/airplane/short.html" : Thrust = m(dot) V Lift = k V^2 A cl Drag = k V^2 A cd where k is...
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    R/C Plane Simulation Software - Tips & Advice Wanted

    Thanks for your reply Cyrus! I'm a total rookie on flight dynamics. I have better understanding of general physics, as I've spent a few years working with AI based games and 3D rendering engines. Honestly, after spending about 30 hours on the net reading about aerodynamics, i felt discouraged...
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    R/C Plane Simulation Software - Tips & Advice Wanted

    I hope i posted on the right forum... I've been considering writing a simple(?) R/C flight simulator for quite some time. After reading about aerodynamics i concluded that a simulation software are bound to make great simplifications, and may only model a subset of the actual physics...
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    How to Drive a P-Channel FET in a Low Voltage Synchronous Buck Converter?

    Thanks for your reply berkeman. I guess this pretty much brings me back to square one again... Darn it, I really wanted to find a short-cut, without spending hours in trial and horror attempts! By the way, many years ago some collegues of mine in Sweden put a lot of time in Echelon...
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    Understanding Electrocution Threshold: The Power of Watts in Killing Humans

    I have a faint memory (and could be wrong) that being wet on the skin increases the chances of surviving in lightning accidents. I guess that's due to the fact that most of the current will flow on the skin rather than through the vital organs.
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    How to Drive a P-Channel FET in a Low Voltage Synchronous Buck Converter?

    berkeman, I did not observer that the original posting whas from 2004 :shy: Yes, i want to remove the freewheeling diode in favor of a N-Channel MOSFET. The design is then basicly just a synhrounous buck converter (as shown in the picture) driven by an mcu generated PWM. I was hoping...
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    How to Drive a P-Channel FET in a Low Voltage Synchronous Buck Converter?

    Good question, have no idea. Perhaps bryce1 can enlihgten us? I'm not looking for 400mV solution, rather a discrete design for driving up and low side with break before make. It seems almost impossible to find some info on discrete solutions. It appears that gate driver chips and PWM...
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    How to Drive a P-Channel FET in a Low Voltage Synchronous Buck Converter?

    Did you ever figure out how to do this with discrete components? I have exactly the same issue, and find no information on the subject... Thanks, Mike
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