stepper motor

Status
Not open for further replies.
W

watzmann

New Member
Hi All ,

i have made a mistake and need to discuss the result with you ,

i have made a new pcb for controlling stepper motor but i forgot to put the diode between the emitter and the collector of the TIP120

that burnt the microcontroller 16f84a

could you please tell me what is the purpose of the diode in the tip120

and how my microcontroller burnt although i have the buffer 4050

what will happen when i neglect it

here is the original the schematic in case you would like to see it

https://www.imagesco.com/articles/picstepper/03.html
 
Last edited:
According to your link:-


From this it looks like you risk destroying the transistors, what makes you think you "burnt" the uC?
 
UTMonkey said:
According to your link:-



From this it looks like you risk destroying the transistors, what makes you think you "burnt" the uC?
Click to expand...

Maybe I'm misreading it, but I thought that meant the exact opposite: that on transistors *without* the internal diode, you'd risk blowing the transistors, but that the TIP120s include it internally and so should be safe. The second paragraph on the linked page has a sentence in boldface specifically stating that you don't need to include the snubber diodes.

So I don't know yet what's wrong here, but I'd look somewhere else first.


Torben
 
those diodes are there to clamp the collector to diode voltage drop. i WOULD PREFER THE DIODES TO BE PUT ACROSS THE COIL as opposed to across the transistor. the question that remains are the diodes fast enough to do the job. if not then the C to B breakdown ocured blowing the whole thing. OR maybe the diodes cannot absorbe the energy from the coil then blewy.
 
I'd check the PCB for errors. I use AVR, mostly Attiny13L, which at 88 cents each, and still learning... I tend to abuse the hell out of them, and haven't damaged one yet.
 
i have one fact now , my microcontrollelr is over......but i wonder why that had happened although i have this stupid IC4050

i have another PCB for the same schematic , it works very well , without the diodes i think all will go wrong like the state i'm in .

have another question : what if i have a stepper motor needs 12 volt , can i cnonnect it's fifth terminal to this 12 Volt ..

or what i have to do

thanks you
 
Are you using the 4050 as buffer between the PIC output and the TIP120's
If Yes, the 4050 isnt suitable for a 12V base connection to the TIP120!!!
 
Status
Not open for further replies.

Similar threads

T
  • Question
Design Help with Out of Spec Stepper Motor
Replies
3
Views
1K
tebiekoud23
T
C
  • Question
Stepper motor solution for a coil winding machine.
Replies
7
Views
1K
MaxHeadRoom78
J
  • Question
Find pulse width for stepper motor
Replies
8
Views
2K
Tony Stewart
J
Stepper Motor voltage spec
Replies
7
Views
2K
MaxHeadRoom78
  • Question
Motor inrush timer
Replies
2
Views
730
throbscottle
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…