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I was completely derailed by an urgent project, but I'm back.

Iron

I haven't implemented any specific pwm 

I havent implemented H bridge yet but was stuck trying to implement simpler configurations first

limited by the amount of current comming out of the micro controller

No specific favorite FET but I'm interested in much smaller motors

Looking forward to another good lecture

Thanks Paul for the informative and wonderful lecture.

Iron

I missed so much helpful info!!!? I'm here to say hi from China to everyone!

Thanks a lot to Paul's wonderful lecture! I've learned too much.

Iron

Thank you Paul, very informative lecture.

Does load affect H-bridge parameters? At which intent?

No motor control with PWM

Thanks Paul, good session

Iron

Thank you Paul, Rob, Design News and Digi-Key.

Iron

Good session Paul, very useful. I'm learning a lot.

Iron

Q: What frequency PWM have you used? I have never implemented such a design.

Iron

Q: Have you implemented H-bridge control? No, I've never implemented H-bridge control.

Iron

Q: Favorite FET? I don't have a favorite FET.

Iron

Back from my meeting, catching up on the lecture now.

Iron

Thanks Paul. And thanks everyone for attending and asking questions. See you tomorrow.

Blogger

OK thanks for listening, see you tomorrow.

Paul.

 

Blogger

Thanks for the explanation on High and Low drives.

Iron

Rmend: I would suspect an indicator as to whether the motor is "on"  Could also be used to determine if the motor is "stalled" (max current draw)

Yes, I very much do recommend looking at the

dead time delay.  If your FETs are hot, it could be

that you've got some shoot-through going on that can

be very easily removed.

Blogger

What function does the OP amp preform in slide 9?

 

Iron

Someone asked earlier, is the data sheet misleading, no I don't

think it is.  I think it helps to understand the nature of the device.

Another area that is often overlooked is the rating of the body diode

in a FET device.  It can matter!  It matters in a power supply with

synchronous rectification and it can matter in a motor controller too.

We just don't have time to take apart the whole fet spec's. in the course.

Blogger

Thanks.. One more question: do you recommend looking at the crossover interval with a dual trace scope to verify the dead time delay is adequate for the drive frequency

Great Presentation Paul

Iron

? slide 26: Is the shunt resistor there to prevent excessive current during shoot thru? What values are typical? 10 Ohms?

cghaba:  FETs can go into the many hundreds of

volts.  Different vendors are best at making fets either

with low voltage process - up to about 75V, or high voltage

processes - up to about 750V,  You will note when you look

that there are distinct jumps in availablility at various voltages.

Below 100V, Below 400V, Below 600V, etc.

Blogger

In actual practice the Q1/Q3 cross-over point should in fact be ZERO.

Yes, that is possible and desireable.

Blogger

Alaskaman66:  The motor never cogs because its a brush motor

and consequently the magnetic field is always right for the motor.

At 30% it will just try to start to run....  Depending on the motor and

the load and friction will move accordingly.... but not cogging.

Blogger

Advantages of Low Side vs High Side Drive:

Low side drive is easier in almost every respect.

Hi side drive however disconnects power from the

device and in certain cases is useful.  When possible,

we'll always look at low side drive first when starting

a new design.

Blogger

? Slide 22: So when driving an H bridge with a PWM train at, say, 30% does the motor cog at the drive frequency? Isn't it running full torque, then braking?

Is this a method for speed control against varying loads?

? Which is the highest voltage a FET can support?

Iron

Thanks Paul, very interesting.  I especially like the practical aspects of your comments.

 

Iron

Thanks Paul Excellent presentation. ? Is it possible in practice to make it such that for example Q1 & Q3 source-drain current crossover point is as close to zero potential as possible to minimize shoot-through?

Hey Paul, How much capacitance do you recommend for bypassing the H-Bridge?  I usually use 100uF per Amp of motor current.

 

Iron

MarEng:  I would not think of it as 'bypassing' the

bridge, I'd think of it as a power reservoir, and manage

the voltage ripple with respect to the load.

Blogger

Thanks for the presentation.

Iron

Okay Paul (pulldowns,) thank you!  :)

 

great presentation and excellent

Platinum

Thank you for the presentation.

Iron

thanks paul for this wonderful section

Platinum

Thank You very much, Paul!

Iron

GREAT presentation. Thanks, very much.

Very good course and will be back tomorow

Yes, no gate pull down R's on 27 because

the driver does that for us... lazy too maybe?

 

Blogger

Lot of info to cover in a short amount of time.  Well done.

Iron

Hey Paul, How much capacitance do you recommend for bypassing the H-Bridge?  I usually use 100uF per Amp.

Iron

Where can I download this audio?

Thanks so much for the presentation!!

Iron

???????

Hello. Can you tell me what are the advantages of using high or low side drive?

Iron

thanks Paul and Rob, see all next day.

Iron

Will have to listen to it again for the parts I missed to day but what I heard was great.

 

Iron

Excellent course.  Thank you.

Thanks Paul.  Good info.

Iron

Paul - thanks again and looking forward to tomorrow

Iron

thanks Paul and Rob

Iron

Very useful! Many thanks Paul and Rob!

Iron

Thank you for the presentation

 

very good presentation, thanks

Iron

No gate pulldown R's on slide 27?

Thanks!  It is real help.

Iron

Thank you Paul, great presentation

Iron

Thank you Paul! excellent lecture.

Iron

Have not done anything using FET PWM applications

We're now on slide 27.

Blogger

Have not done anything with a fet using PWM

Iron

We're now on slide 25.

Blogger

We're now on slide 24.

Blogger

We're now on slide 23.

Blogger

We're now on slide 22.

Blogger

12KHz, 18KHz, 20KHz.

Just motors.

Iron

I did one at 10KHz.  Noise was not an issue with this application.

Iron

no motor control apps yet.

Iron

Paul's question:

Have you made use of PWM control, and if so at what frequency have you used?  Anyone over 50KHz or under 10KHz for a brush motor  application?

Blogger

We're now on slide 21.

Blogger

We're now on slide 20.

Blogger

We're now on slide 19.

Blogger

We're now on slide 18.

Blogger

We're now on slide 17.

Blogger

We're now on slide 16.

Blogger

We's now on slide 15.

Blogger

Yes, 90V for up to 2HP motor

Iron

I've used H-bridge control for personal projects of 12V and a version of H at 80VDC

Iron

We're now on slide 14.

Blogger

Yes.  Low power (12VDC @ appx 1A).

Iron

You mentioned that a DC brush motor can brake with a single FET....how?

Iron

no H-Bridge control, just high side SS Relay control or power FET

Iron

Yes to H-bridge control. Low power servo motors.

Gold

Yes, running 24VDC up to 4 Amps.

Iron

@MazianLab - The heat is from the power of current * Rdson.

Iron

Paul's question:

 

Have you implemented H-bridge motor control and if so, at what power level?

Blogger

Paul! Is there any heat generating by taransister when pulling maximum current? 

Iron

We're now on slide 12.

Blogger

We're on slide 11 now.

Blogger
@jdsb@ggis.net = Is the sound on your computer muted?

. Note that some companies block live audio streams. If when the show starts you don't hear any audio, try refreshing your browser. If that doesn't work, try using Firefox or Google Chrome as your browser. Some users experience audio interruptions with IE. If that doesn't work, the class will be archived immediately following our live taping.

Blogger

looking at IRL2703SPBF

Iron

We're on slide 10 now.

Blogger

We're now on slide nine.

Blogger

jdsb@ggis.net @ please refresh your brwoser.

Iron

No audio or video.

 

Iron

I have had a couple i've used But can't remember the number has been a couple of years but they were IR devices 

Iron

These type of transistors are used for battery charging very much.

Iron

How do I get the audio to play? I can SEE things, but no audio.

 

2N7000 series is my most commonly used part for low level control, no motor control, just signal.

Iron

We tend to be an International Rectifier house. Specific part number depends on application.

Iron

It depends on design.

Iron

We're now on slide seven.

Blogger

IR components are good.  Fairchild FDB8441 is also.

Iron

I use drv8801 from TI

 

Iron

Not particulary, depends on design

Iron

We're now on slide six.

Blogger

Paul's question:

Do you have a fovorite FET device, and if so, please tell us, what is your favorite - your goto - FET for your applications?  Vendor, Part Number?

Blogger

We're now on slide five.

 

Blogger

The FET spec sheet is misleading.  The "Silicon Limited" current is meaningless.  Only the lower value "Package Limited" is relevant since the part is in a package.

Iron

Check out International Rectifier

We're now on slide four.

Blogger

We're now on slide three.

Blogger

Audio is clear. Thanks

Iron

We're now on slide two.

Blogger

Good afternoon, everyone

Iron

Click on the right arrow.

ok, i hear the talk.

Iron

Hello from Toronto!!!

Iron

Hello from rainy NY.

Iron

Hi all -Audio is live! If you don't see the audio bar at the top of the screen, please refresh your browser. It may take a couple tries. When you see the audio bar, hit the play button. If you experience audio interruptions and are using IE, try using FF or Chrome as your browser. Many people experience issues with IE. ALso, make sure your flash player is updated with the current version. some companies block live audio streams, so if that is the case for your company, the class will be archived on thsi page immediately following the class and you can listen then.

Good morning from Reno, NV.

Iron

will the audio start on itself ? or must i do something to hear it ?

melotte joseph

Iron

another few second to strat this section

Platinum

Good afternoon from Wichita, KS

 

Audio will start in a few minutes. You need to click on the audio bar that will appear where it says "You are signed up for this lecture"

Melotte -- you'll hear video when it begins in a minute.

Blogger

Hi from Andover, MN.

 

Iron

The audio will begin at 2pm

 

Iron

We're about to begin. About two minutes.

Blogger

i am onliner;

i saw  the slides.

what should i do now to start hearing  the webinar ?

i don't see what i have to do.

 

Melotte Joseph

 

Iron

Greetings from Atlanta, GA

Iron

Hello from Albuquerque

Iron

Rats... Another meeting scheduled coincident with our class. I'll have to catch up afterwards.

Iron

another 10 minutes to start

Platinum

Good afternoon or morning,

 

Iron

hello from Mishawaka

Iron

hello all from Edmonton, Alberta

Iron

Greetings from senic Midland Tx.

Iron

Hello From Morgan Hill CA

Good to see everyone. Hi MyDesign. 

Blogger

Hello from Montana

Gold

-The streaming audio player will appear on this web page when the show starts at 2 PM Eastern time today. Note however that some companies block live audio streams. If when the show starts you don't hear any audio, try refreshing your browser. If that doesn't work, try using Firefox or Google Chrome as your browser. Some users experience audio interruptions with IE. If that doesn't work, the class will be archived immediately following our live taping.

Blogger

I hope I win the $25 starbuck gift card. 

Iron

Greetings from Colorado Springs - where flash floods, bright sun, and hail make the weather forecasters almost always wrong...

Iron

brushless dc motor driving circuit is one of my intresting topics

Platinum

Hello from SW Michigan

Iron

-Be sure to click 'Today's Slide Deck' under Special Educational Materials above right to download the PowerPoint for today's session.

Blogger

Good morning from California!

Iron

Data sheet for the FET

http://www.irf.com/product-info/datasheets/data/irfs3107pbf.pdf

fyi

Iron

Hello from SE Lake Simcoe Ontario Canada. Another unusually chilly summer day here.

Iron

Hello from Iasi, Romania

Iron

-Please join our Digi-Key Continuing Education Center LinkedIn Group at http://linkd.in/yoNGeY

Blogger

Hello from Chicasgo

Iron

Good morning from Chicago!

Iron

Hi everyone, from Chihuahua, Mexico

Iron

Good afternoon from Maryland. Looks like its going to be fun class today..

Iron

Hi everyone, good morning.

Iron

Hello from Beaverton, Oregon.

Iron

Good morning from rainy Panama City, FL.

Iron

-Be sure to follow @designnews and @DigiKeyCEC on Twitter for the latest class information. We encourage you to tweet about today's class using the ha.shtag #CEC

Blogger

Good morning from Albuquerque, New Mexico.

Blogger

Good morning from Edmonton, AB

Iron

Morning from Porltand Oregon

Iron

Good morning from Mobile, AL

Hi,

Good morning from Toronto, Canada

Iron

@jmelotte, you can translate to your local time using sites such as e.g. worldtimeserver.com

dear,

 

2.00 PM EDT, is this corresponding to 8.00 PM time in Brussels ?

can you confirm me this very soon, urgently.

with thanks,

melotte joseph

 

Iron

Oh goody -- a topic I know nothing about!

Hello from cloudy SE Lake Simcoe, Ontario Canada

Iron

Mid August, and all's well.



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