H-bridge suggestion for this type of DC motor?

[lloydi12345]

Hi, I would like to control two of these motors Mabuchi Electric Motor RS-380PH. Here's how it looks like: **broken link removed**

I also got its datasheet. Here: https://www.electro-tech-online.com/custompdfs/2011/01/rs_380ph.pdf

Can you help me what's best h-bridge driver controller for this? I'm planning to use L293D (I don't know if it will be burnt quickly), L298, transistors using TIP41 NPN and TIP42 PNP. My power source will be a Panasonic 6v 4A Lead Acid battery. I will drive a 1/15 rc tank. Thank you

Edit: I would like also to aim for convenience. I hope you can help me with this.

 

[4pyros]

The L298 should work for this motor. Put it on a good heat sink. Andy

 

[ronv]

That is a beefy little motor. When stalled it will try to draw over 10 amps at 6 volts. So even if you parallel the 2 bridges in the L298 you won't be able to stall your tank because the LM298 is only good for 4 amps. Having said that the voltage drop of the 298 is 4.9 volts at 2 amps so with a 6 volt battery you won't be able to get more that a couple of amps thru the motor. The bottom line is it may work but its going to be more like a heater than a motor.
I'm not sure there is an ic solution for your application. It may take a discrete FET bridge. You could use a 12 volt battery and current limit the LM298 and at least then you could get more power from the motor.

 

[lloydi12345]

That is a beefy little motor. When stalled it will try to draw over 10 amps at 6 volts. So even if you parallel the 2 bridges in the L298 you won't be able to stall your tank because the LM298 is only good for 4 amps. Having said that the voltage drop of the 298 is 4.9 volts at 2 amps so with a 6 volt battery you won't be able to get more that a couple of amps thru the motor. The bottom line is it may work but its going to be more like a heater than a motor.
I'm not sure there is an ic solution for your application. It may take a discrete FET bridge. You could use a 12 volt battery and current limit the LM298 and at least then you could get more power from the motor.

Oh ronv, sorry I don't get it, what I mean is those are my choices. If what's better H-bridge chip L298 or H-bridge with Tip42 and Tip41. Andy suggested L298, how about yours?

 

[Boncuk]

The data for both motors show a much higher current demand than the L298 can supply!

The RS-380PH-4045 requires 21.4A and the RS-380PH-3270 requires 14A.

With or without heat sink you'll fry the L298 instantaneously upon start up.

Better use high current power MosFet transistors capable of at least 40A of current flow.

Boncuk

 

[Boncuk]

The L298 should work for this motor. Put it on a good heat sink. Andy

Did you read the motor data?

They require 21.4A for the 10.5V type and 14.0A for the 12V type respectively.

The L298 is good up to 4A!

Boncuk

 

[4pyros]

Did you read the motor data?

They require 21.4A for the 10.5V type and 14.0A for the 12V type respectively.

The L298 is good up to 4A!

Boncuk

Sorry I did not look at the spec sheet at first, the ebay page had currents in the MA. range, So ya the L298 chip is not a good one to use, it may work for testing. If you look on the robot sites thare are many H drivers out thare. Andy

 

[lloydi12345]

Thanks for clarification Boncuk, Hi, I'm really not familiar about the PCB design of the custom made RC tanks. Do you have any idea if they are using driver chips than Hbridges made from transistors? Because I think it will use most of the space inside the tank if i'll use these transistors.

EDIT: How about also if I use TIP42 and TIP41? I don't really get what's the difference with Bipolar and MOSFET transistors. Sorry

 

[4pyros]

I'm really not familiar about the PCB design of the custom made RC tanks. Do you have any idea if they are using driver chips than Hbridges made from transistors?

take a look at some of the offerings on the web.

 

[Boncuk]

Hi lloydi,

there are ready made high power motor control circuits fitting right into the the R/C system instead of a servo.

Just google for model tanks and you'll find everything you need.

They control forward and backward speed of vehicles like tanks and cars digitally and proportionally.

BTW, MosFet transistors dissipate less power than bipolar transistors, hence making more power available to the motor.

Boncuk

 

[stephen87]

**broken link removed** just a tutorial on a dc motor drive with a H bridge driver l298.

 

[lloydi12345]

Thanks for your replies Andy, Boncuk, Stephen87. I'm already exposed at BJT transistors for h-bridges. I already used them on my previous projects. I'm not yet familiar if it's also using PnP or NPN types. I don't know if the same concept is applied on MOSFET dc motor drivers. Here's what I found. I've read that MOSFETs have internal diodes. He's using RFD3055. I have some questions.

1. Will this be fine even without external diodes?
2. If I can't find this type of mosfets on our local stores, what substitutions will I look for? Power MOSFETs?
3. What should I check also on the datasheet? Is it the current drain?

Thanks a lot.

 

[audioguru]

The Mosfet H-bridge will not work
1) The Mosfets selected need 10V between the gate and source to properly turn on. The lower Mosfets get only 5V.
2) The upper Mosfets get nothing because for the source to be pulled up to +5V then the gate must be +15V which is impossible.

Usually P-channel Mosfets are used for the upper mosfets so that they turn on when the gate goes to ground.
All Mosfets must be the 'logic-level" type that properly turn on when the gate-source voltage is only 5V (ordinary Mosfets need 10V).

 

[4pyros]

Will this be fine even without external diodes?

You Must have the diodes to protect the Mosfets from back EMF from the motor. Andy

 

[lloydi12345]

Hi,I really can't find any mosfet h-bridge driver chips
I'm looking at the list here:
**broken link removed**
This is the only store in Philippines that has an online shop with a lot of driver ICs and ships products around our country. This is my only option since in our province the shops here don't sell those kind of stuffs. I hope you could help me check there.

I was thinking if I can use this one:
TPS2812 DUAL HIGH-SPEED MOSFET DRIVERS
Is this right?
I got its datasheet right here: http://www.datasheetcatalog.org/datasheet/texasinstruments/tps2812.pdf

I really wanted to save space for our RC tank. It already gets crowded if I'll make a board of H-bridge. I'm using 2 6v 4A Lead Acid batteries that eats up a lot of space.


Anyway, I tried creating this MOSFET h-bridge based from the basic schematics. I can see it turning on with my PIC.

 

[Boncuk]

Hi lloydi,

here is a motor controller with very small dimensions. It measures 41X35X15mm (1.6X1.4X0.6") and has a weight of 83gram. It controls 12V motors up to 50A (60A peak).

The enclosure is completely water tight.

It has the order number 226 994 - 62 at Conrad - Online Shop f

The price €49.95 (approx. US$60).

Here are an image and the user's guide (also containing English).

Boncuk

 

[lloydi12345]

Hi lloydi,

here is a motor controller with very small dimensions. It measures 41X35X15mm (1.6X1.4X0.6") and has a weight of 83gram. It controls 12V motors up to 50A (60A peak).

The enclosure is completely water tight.

It has the order number 226 994 - 62 at Conrad - Online Shop f

The price €49.95 (approx. US$60).

Here are an image and the user's guide (also containing English).

Boncuk

Thank you for the reply Boncuk, guess like I have to do it on my own. Shipping takes a lot of time.

Can someone so kind help me how to choose the right P-channel and N-channel? What will I look at in terms of my case? I would like to power my dc motors efficiently without something wasted.

 

[lloydi12345]

I've also made another alternative H-bridge made from BJT but with higher current ratings.. Hope to see your feedbacks.. Thank you very much

 

[audioguru]

I've also made another alternative H-bridge made from BJT but with higher current ratings.. Hope to see your feedbacks.

1) Your motor draws 10A to 22A but the power transistors you selected have a max allowed current of only 6A.
2) Your 330 ohm resistors provide a base current to the power transistors of less than 14mA but the datasheet for the power transistors shows a base current of 600mA for only 6A output. The little 2N3904 transistors cannot provide 600mA if the resistor value is reduced.
3) The datasheet for the output transistors shows that when they have a base current of 600mA and an output current of only 6A then their saturation voltage loss is 1.5V each for a total loss of 3V. The low voltage might stall the motors when you try to start them.

Post a video of the overloaded transistors blowing up.

 

[Boncuk]

I guess it will take more time to get your circuit working than shipping time will take for a functioning unit.

Small items are normally transported via air-mail and don't take more than one week from Germany to the Phillipines.

I have received mail from Germany addressed to me living in Thailand within four days.

Forget about your under-powered circuit and stick to a ready-to-go design.

Boncuk