New hi-speed project

[What's_nitro?]

Switching speed would be the sum of the on-state current rise/fall times.

IE: Rise = 4uS, Fall = 3uS. Total = 7uS so 1S/7uS = 142857.blah blah blah which is about 142 kHz.

[lutach]

Originally Posted by BrianG

You can use a pistol radio with the existing setup - with a bit of tweaking. But I wouldn't want to use electrical brakes with voltages that high...

I did make it work with my pistol radio, but my vehicle has no option for mechanical brake. I like the brake that a car ESC have and if my brake system doesn't come to reality then the controller will have to offer me some braking to slow the car to a safe speed. Is this
(Resistive Switching Characteristics) where I look for the Switching Speed in the datasheet?

[What's_nitro?]

It should be listed under the "dynamic characteristics" table.

[lutach]

Let me see the FDS5672 has a Rise Time of 20ns and a Fall Time of 14ns. The 60V MOSFET that I would like has a Rise Time of 15ns and a Fall Time of 5.5ns.

[What's_nitro?]

Oo nS! I like it! That would be ~29 MHz for the first one and ~48 MHz for the second.

[BrianG]

Me too! Get it done man!

[lutach]

Originally Posted by What's_nitro?

Oo nS! I like it!

Is that good? If so I might just ask the MFG for enough samples to make 2 HV110 and extra if some fail.

[What's_nitro?]

Billionths of a second is good. It means you could run higher-pole motors at higher speeds without cogging like the BK controllers.

[lutach]

You guys are going to turn me into an genius , but I do have to go with what Patrick says. If he gives the OK, then I'll try and get some stock on them. The 100V one I know there's stock of it, and the Tr is 15ns and the Tf is 9.3ns and will 0.01ohm make much difference?

[lutach]

Originally Posted by What's_nitro?

Billionths of a second is good. It means you could run higher-pole motors at higher speeds without cogging like the BK controllers.

I love learning new things. Too bad I can't make ESC and just thinking if I could, this hobby would get dangerous very quick. I hate to be the reason the government ban our R/C goodies.

[What's_nitro?]

What is the current rating on the 100V? It's hard to say if the 0.01 ohm will matter, since there is usually less current flowing in a HV system the losses would be about the same as a LV but HC system with a lower resistance FET. Although 0.01 is about 5 times higher than average Rds for a FET.

[lutach]

Originally Posted by What's_nitro?

What is the current rating on the 100V? It's hard to say if the 0.01 ohm will matter, since there is usually less current flowing in a HV system the losses would be about the same as a LV but HC system with a lower resistance FET. Although 0.01 is about 5 times higher than average Rds for a FET.

The 100V has the following specs: 100V, 34A cont., 0.023ohms, Tr is 15ns and the Tf is 9.3ns. The FDS5672 has a Rds of 0.01. SO would 0.013 make a lot of differance?

[What's_nitro?]

Compared to the 0.01ohm that 0.013ohm would be 30% higher resistance and so 30% higher losses at a set current. A 10W loss would become a 13W loss and so forth. Since you would have a bunch of them in parallel to handle motor current it wont matter too much. I take it you would get a smokin' deal on these FETs- is that why you're so interested in them a not one with a lower Rds?

[lutach]

Originally Posted by What's_nitro?

Compared to the 0.01ohm that 0.013ohm would be 30% higher resistance and so 30% higher losses at a set current. A 10W loss would become a 13W loss and so forth. Since you would have a bunch of them in parallel to handle motor current it wont matter too much. I take it you would get a smokin' deal on these FETs- is that why you're so interested in them a not one with a lower Rds?

I won't buy them from the MFG just yet because it's really low QTY. When I do buy for my clients, it's really large QTYs and my prices are incredible. I'll buy them from whoever has stock and only the 100V one is showing in stock. I will have to check a couple more distributors to see if they have them. I'm going to see if I can get samples of the 60V one ASAP, if not the 100V will have to do.

[What's_nitro?]

Well a 23s controller would be pretty awesome...with 8p per phase you could easily put 10KW through that thing!