pic and motor control

[UnD3aD]

Is this scheme enough to not burn my pic? i need a simple controller for a small motor

 

[Jay.slovak]

You are missing Base Resistor!!!
Try 1K as a start value..

 

[Nigel Goodwin]

Is this scheme enough to not burn my pic? i need a simple controller for a small motor

No, that wouldn't work - and would probably blow the PIC (and the transistor). You should use an NPN transistor with the motor in the positive supply to the collector - check my tutorials under 'hardware Extras' for examples.

 

[Jay.slovak]

Is this scheme enough to not burn my pic? i need a simple controller for a small motor

No, that wouldn't work - and would probably blow the PIC (and the transistor). You should use an NPN transistor with the motor in the positive supply to the collector - check my tutorials under 'hardware Extras' for examples.

Yes, that 9 volts IS a problem... didn't notice that.

 

[Someone Electro]

Heres what to corect:
-A resistor betwen the PIC and the base(1K-10K)
-Motor above the thasistor
-NPN trasistor

 

[UnD3aD]

tnx for the replays guys... the next one is ok? The diode is fine?
and one more question:
can i create PWM in the software? coz i have ony one PWM channel and i need to control 2 motors.. and what difference is between the PIC PWM and the one that i create in the soft? the acuracy?

 

[Jay.slovak]

No, the resistor has to be in the BASE of the transistor (and the schematic symbol does not belong to NPN, but to PNP). The rest is ok.
And yes, you can create additional PWMs in software. Software PWM is generaly slower and requires more resources.

 

[UnD3aD]

oh.. ok.. ty guys...

 

[Nigel Goodwin]

oh.. ok.. ty guys...

You've obviously not looked at the 'Hardware Extras' section of my tutorial as I suggested previously, where it shows EXACTLY the circuit you need (with a relay instead of a motor).

 

[UnD3aD]

i really didn't find the hardware extras and the tutorials...

 

[Nigel Goodwin]

i really didn't find the hardware extras and the tutorials...

It couldn't be much easier to find?, but here's the exact page .

 

[UnD3aD]

i searched in the 2nd site..
verry usefull tutorial... tnx

 

[UnD3aD]

i have a problem now... i made the circuit and it's not working... the motor is spinning only if i help it in the beginning and i spin it a few times.. then the motor is working... but the transistor goes very hot.. i use a 9v battery at 1 Ampere (regulated at 5v with 7805), pic 16f628a, bc547 NPN transistor (60v , 0.2A), 4148 diode, a small motor, 700 ohms resistor

 

[upand_at_them]

A 9V battery can't supply 1A; I think it's more like half that.

Mike

 

[Pommie]

Can you post your schematic again?

Mike.

 

[UnD3aD]

scheme

 

[Nigel Goodwin]

scheme

That looks fine, although I'm a little puzzled about the strange value of 700 ohms?.

You should also try posting your diagrams in a better format, JPG is fine for photos, but useless at diagrams - if you post it as a GIF it will be far smaller, and not lose any quality.

 

[UnD3aD]

With a resistor >700 ohms it doesn't work.... The transistor is the problem? it have only 0.2A...

 

[Nigel Goodwin]

With a resistor >700 ohms it doesn't work.... The transistor is the problem? it have only 0.2A...

So what's wrong with 680 ohms?. 680 ohms is an E12 value, 700 isn't even an E24 one!.