Help regarding H briges.....

[koolguy]

You said;

I am using IRF9540 AND IRF540..and i am ready to use transistor.

This circuit dose not use transistors.

Yeah I said but i don't found any some one has provided this schematic....!!

 

[ericgibbs]

Yeah I said but i don't found any some one has provided this schematic....!!

This is your part circuit completed, it works in simulation OK.

I have never built this particular circuit, so I cannot confirm that it works, it should do.

The MOSFET Vgs is 0v to 12V , relative, well inside the +/-20V limit

 

[audioguru]

Who suggested not to use them and why.??

It was me on another website. I don't know if a modern PIC has enough output current to drive a very old original 74xx TTL logic inverter.

I think the P-channel Mosfet will blow up with a gate-source voltage of 24V.

 

[koolguy]

The circuit is working fine....
One problem is there i.e. when i stop the motor it does start quickly as it was working with direct power source and some noise is also cumming from motor ...and i am not using Capacitor as shown in upper side of P- MOS!!

 

[audioguru]

I anwered this on the other website 15 seconds ago.

 

[ericgibbs]

It was me on another website. I don't know if a modern PIC has enough output current to drive a very old original 74xx TTL logic inverter.

I think the P-channel Mosfet will blow up with a gate-source voltage of 24V.

hi agu,
Its not an old original 74xx, its a 74LS and yes the PIC can drive it quite well.

On the revised circuit, the maximum Vgs is ~16V so it will not blow up.

I did say I would have to modify the resistive divider, once I knew what the OP wanted.

Checking the datasheets you have posted, the +/-20Vgs limit does apply. It will be necessary to limit the Vgs on the MOSFET's to less than this value.

**broken link removed**

 

[audioguru]

hi agu,
Its not an old original 74xx, its a 74LS and yes the PIC can drive it quite well.

But we don't know if a 30 years old lower input current 74LSxxx IC is available yet in India.
The OP was talking about a 40 years old ORDINARY 7406 mor 7407 with a VERY high input current. Probably a modern PIC IC cannot drive it.

 

[koolguy]

Hi,

did say I would have to modify the resistive divider, once I knew what the OP wanted.

Yes sure if you want to do any correction in it you are welcome........!!

 

[4pyros]

Hi,

Yes sure if you want to do any correction in it you are welcome........!!

He already did!!!

 

[ericgibbs]

But we don't know if a 30 years old lower input current 74LSxxx IC is available yet in India.
The OP was talking about a 40 years old ORDINARY 7406 mor 7407 with a VERY high input current. Probably a modern PIC IC cannot drive it.

If we DONT know if 74LS can be bought or not in Asia, WHY bring it up.?????

The OP may have been talking about 74xx, but my circuit clearly shows 74LS.

The OP did ask for a version that used IC's as drivers to the MOSFET's, rather than transistors, that is why I posted the 74LSxx circuit.

EDIT:
I will do some tests with a PIC and 74xx,74LSxx and post the the results.

 

[ericgibbs]

Hi,

Yes sure if you want to do any correction in it you are welcome........!!

Ritesh,
Look here,
https://www.electro-tech-online.com/blogs/ericgibbs/202-24v-h-bridge-mosfets-ics.html

I understand that you are now using the LM339 version of the drivers, is that correct.?

 

[koolguy]

HI again,

Today i have tested the H-BRIDGES with 12V and 12V series connection i.e. 24V with PMDC motor.
The maximum current that i have seen seen on multimeter is 6-7Amp that was the limited current from battery.

OK, when i have used Brushed DC gear motor at 24V and switching the freq (of 555 using pot meter) to the input of LM339 as shown in circuit before.
there was lot of spark at the brushes at low freq. so i think it require snubber circuit at motor terminal.
So, please suggest how to build snubber circuit.

 

[ericgibbs]

hi agu,
Programmed a 16F877 PIC, powered by +5V, to toggle an output pin.

Tested the following IC,s
NOTE:
all 6 inputs linked together to give a Fan in of 6, output driving an resistor/led, all OK.
It also worked OK, with a fan in of 1 gate.

7404,7414,74LS14,7404,74LS04,,7406,74LS06.

The PIC output pin voltage was switching from 0.1V to 4.9V on all the IC's. OK.

Added a 300R and Rd led to the PIC output pin [IC still connected] , switching from 0.1V to 4.2V

I would say that a PIC operating from a Vs of +5V, will drive 74xx and 74LSxx IC's satisfactorily .

Do you agree.???

If yes, please let us put another web based Myth to rest, if No, try it yourself.

Eric

 

[koolguy]

This is your part circuit completed, it works in simulation OK.

I have never built this particular circuit, so I cannot confirm that it works, it should do.

The MOSFET Vgs is 0v to 12V , relative, well inside the +/-20V limit

Hi eric,

If you have this schematic LT spice file can you please post it as i have to present my circuit ( mos IRF9540/540).

Thanks

 

[ericgibbs]

Hi eric,

If you have this schematic LT spice file can you please post it as i have to present my circuit ( mos IRF9540/540).

Thanks

hi,
Its in my Blog, look here. https://www.electro-tech-online.com/blogs/ericgibbs/202-24v-h-bridge-mosfets-ics.html

EDIT added.