pic MC

[Elecman2000]

Is it necessary to use Two power supplies separated , one for the pic and the other for the load, or One is enough and separating the two circuits by opto ???

 

[ronsimpson]

What load?
Not enough information.

If your load needs the same voltage as the PIC then use one supply.

 

[Elecman2000]

What load?
Not enough information.

If your load needs the same voltage as the PIC then use one supply.

Not same level offcourse,, 2 motors, 24 volt , 110 rpm each, Amper is unknown , i bought it used motors, no info about the ampere,, this is the one i bought
http://www.motors.wrobots.com/matsushita-GMN6MP026A.php

 

[Elecman2000]

any help?

 

[ronsimpson]

Power the PIC from a 5 volt supply. (3.3V)
Power the motors form a 24 volt supply.
Connect the two grounds together.

You can also use a LM7805 to change 24V into 5V. That way everything can run from 24V.

 

[Elecman2000]

Power the PIC from a 5 volt supply. (3.3V)
Power the motors form a 24 volt supply.
Connect the two grounds together.

You can also use a LM7805 to change 24V into 5V. That way everything can run from 24V.

ok thx for help man

 

[Wilksey]

Wooo, don't forget the heatsink!!

24V to 5V is a pretty hefty power dissipation task for a linear reg!

I would use a DC-DC converter, or switching reg as they are sometimes known.

I would drive the motors using FET's correctly rated, or, an automotive relay. I would chose the relay personally, no heat to dissipate.

Just my 2 pence worth!

Wilksey

 

[Wilksey]

Quick find: **broken link removed**

Shows 67.7W for that motor which is just over 3 amps at 22V.

 

[sukarthi]

LCD program

hi now am doing program to display string on lcd using micro controller can anyone give the coding of that

 

[Ian Rogers]

hi now am doing program to display string on lcd using micro controller can anyone give the coding of that

Determined.. I'll give you that...

There are LCD tutorials, in C on this forum... There is a link in my signature.

 

[sukarthi]

thank u for ur reply ......but am asking to send string data on lcd by using micro controller 8051.

 

[Ian Rogers]

When you post.... Try to start a new thread...... When you hi-jack someone else's thread.. People tend to ignore you...

There is a 8051 section for this processor and you will get more people looking at the post.

You should include as much info as possible..... MCU type... LCD you need to use.... CODE choice asm... c pascal etc....
Some people here are very good... but cannot read minds.

 

[Elecman2000]

I would drive the motors using FET's correctly rated, or, an automotive relay. I would chose the relay personally, no heat to dissipate.

Just my 2 pence worth!

Wilksey

I made h-bridge by tip 122 and 127, one of them exploded it got so freakin hot, no wrong made in the connection ,,, A relay would be the right selection, but does this mean that high power transister is not reliable in such application ?

 

[ronsimpson]

I made h-bridge by tip 122 and 127, one of them exploded it got so freakin hot, no wrong made in the connection ,,, A relay would be the right selection, but does this mean that high power transister is not reliable in such application ?

We need more information! I know you are using TIP122/127. I do not know how you used these parts. The how is very important.

 

[Elecman2000]

We need more information!

see the circuit i got it from this link
**broken link removed**

i made the the circuit as in the attach, the motors are 24 but i used 12

 

[ronsimpson]

It looks like you connected the base of Q5 to the base of Q6. That will kill a transistor.

 

[Elecman2000]

It looks like you connected the base of Q5 to the base of Q6. That will kill a transistor.

how i control this circuit with 2 signals ?

 

[Wilksey]

Ron is correct, that will kill your transistor.

FETs are OK, if they are correctly spec'd.

https://en.wikipedia.org/wiki/H_bridge

The projects part of the Wiki page shows how to drive a HBridge.

 

[ronsimpson]

There are H bridge ICs. Many different types. Some have 4 or 3 or 2 inputs, with different logic. You should look at them.

 

[Elecman2000]

OK thx for heLP