Lebowski
10 MW
I've had it up to 98000 erpm, don't know how high Arlo went...Tek said:Make it reasonably priced and I will also be down. BTW what is max e-rpm?
I've had it up to 98000 erpm, don't know how high Arlo went...Tek said:Make it reasonably priced and I will also be down. BTW what is max e-rpm?
I don't understand the meaning of that sentence. What power supply issues are there when using isolated supplies?zombiess said:I think that's a good idea and eliminates the power supply issues since everything I am designing is using isolated supplies.
Pruple jeep is busy with something like that, AFAIK his end goal is a controller box combined with a salvaged Honda Hybrid power stage...Tek said:98000 erpm? Oh, I like where this is headed...I like it a lot!
Is there anything stopping us from having a 2 box system? Like one control box, and one power stage that can be any size we desire?
liveforphysics said:MOSFET's are good enough now that IGBT's days are numbered IMHO. Eating the Vf drop as heat becomes impractical and silly at some point.
You slow down the other FET switching on... or just prevent the diode from turning on...zombiess said:MOSFETs tend to switch really fast and have fast recovery. These are all good things, except if you are trying to meet emi spec. Yes you can slow down the switch times but how does one slow down the diode?
Lebowski said:When i was thinking about using this 150V 100mA device, I was considering a 2 stage approach. Use this one to step down to around 60V, the 100mA means there's about 6W available from 60V. Use a second more low voltage 500mA device to make 5V out of 60, this is about 2.5W. Another one can make 15V at 200mA, taking 3W.
If you make the small power pcb like this you have the option of leaving out the 150V device if your battery is 48V...
Not quite new, but have been well hidden in their parametric searches. Is 250mA any good then?MILPITAS, CA - February 4, 2014 - Linear Technology announces the LTC3638...
Futterama said:Not quite new, but have been well hidden in their parametric searches. Is 250mA any good then?MILPITAS, CA - February 4, 2014 - Linear Technology announces the LTC3638...
I'm too old for this nonsenceFutterama said:Holy cow, Lebowski, are you going the SMD route now? Congratulations!
The MS16 package the Linear devices come in, has real tiny pins, but I managed to solder it on a homemade PCB without soldermask, so it should be easy to solder it on a professional made PCB. The only tricky part is the thermal pad underneath, but I guess a big via could be used to solder through. What I did was add flux to the thermal pad and then add a bit of solder to the PCB area and keep the PCB solder hot while sticking the IC on the hot solder. The only thing that can go wrong is adding too much solder so it will squeeze out and short the pins, but it worked fine for me in my first try 8)
thanks but I have a friend here who's also into SMD's, so it should be ok...Futterama said:Then send me the board and SMD components and I'll solder it for you and send it back. Seriously. I would do that for you.
Lebowski said:I'm too old for this nonsenceFutterama said:Holy cow, Lebowski, are you going the SMD route now? Congratulations!
The MS16 package the Linear devices come in, has real tiny pins, but I managed to solder it on a homemade PCB without soldermask, so it should be easy to solder it on a professional made PCB. The only tricky part is the thermal pad underneath, but I guess a big via could be used to solder through. What I did was add flux to the thermal pad and then add a bit of solder to the PCB area and keep the PCB solder hot while sticking the IC on the hot solder. The only thing that can go wrong is adding too much solder so it will squeeze out and short the pins, but it worked fine for me in my first try 8)
bowlofsalad said:I think I like the idea of having the mosfets separate from the rest of the controller. I ponder the idea of methods keeping the mosfets extremely cool but that often leads me to involving the entire controller. I don't know if anything else in the controller gets warm at all, but I am sure that the mosfets get pretty warm.
zombiess said:bowlofsalad said:I think I like the idea of having the mosfets separate from the rest of the controller. I ponder the idea of methods keeping the mosfets extremely cool but that often leads me to involving the entire controller. I don't know if anything else in the controller gets warm at all, but I am sure that the mosfets get pretty warm.
Keeping MOSFETs cool is actually not very hard. The hard part is designing an optimal layout for the gate driver and power stage while still allowing good cooling. I like to lay the MOSFETs flat. This allows for the best use of surface area for passive cooling and heat distribution while allowing me to obey the gate drive/power stage best practices. If I need to increase power density, then water cooling could become an option, but that comes at the cost of increased complexity, cost and most likely more overall weight, but the gain is lower volume.