Help in feed input of sensor with PNP output to controller (pic16f877a)

[anroop]

i have bought a sensor with 12 v dc input and NPN output (0 v). It must be connected to a controller (max input 5 v)to sense it. i used lm7805 regulator to convert 12v to 5v.
the way i connected it is (to LM7805): input - 12 vdc (from SMPS). Gnd - output from semsor, output to controller. I also connected a stepper motor (12 vdc) & controller (5 vdc) to same SMPS. the fault is that the regulator gets heated too much (couldn't touch it after 5 seconds) while the circuit is switched ON. do you have any other solutions for overcoming this or suggestr any other ways.

 

[KrisBlueNZ]

I can't follow your description. Please post a schematic.

Please include the part number of the sensor, so we know what we're dealing with.

 

[anroop]

i have uploaded the schematic. my problem is that the regulator (lm7805) gets heated. output of sensor is 100 mA.

 

[(*steve*)]

The only things I can see wrong with that are:

1) No ground connection to motor drive circuit
2) No ground connection to controller.
3) Connection between sensor and voltage regulator seems unusual (what function should it serve?)
4) Controller seems to be connected to nothing (what does it control?)
5) Motor driver not connected to a motor, or even a controller.

Apart from that it all makes sense.

Oh, I see what you're trying to do with the regulator. That's not going to work.

Give links to all the components your using (sensor, controller, driver, and motor) and let us see how they're supposed to be connected.

 

[anroop]

please find attachment F.Y.I.

 

[anroop]

1) I don't have link to the sensor. It is NPN ouput (12v). 12VDC input, led type reflective sensor.
2) PIC16F877A
3) stepper motor 12v, 1A , bipolar.
4) motor driver : see atachnment

 

[KrisBlueNZ]

What's the sensor's part number? Manufacturer? Where did you get it?

The diagrams you've uploaded are block diagrams. If you need more specific help you may need to provide a more specific diagram, i.e. a schematic.