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Electronics => Electronics => Topic started by: ed1380 on February 17, 2008, 08:37:28 PM

Title: verify scematic plz
Post by: ed1380 on February 17, 2008, 08:37:28 PM

I'm about to make this. (see pic)

am i forgetting any resistors, diodes, etc?

and i got a question. datasheet says maximum imput and supply voltage 7v. maximum output  60v. how does that happen?

(http://www.societyofrobots.com/robotforum/index.php?action=dlattach;topic=3266.0;attach=1368)
Title: Re: IC pin help
Post by: Joe on February 17, 2008, 09:19:23 PM
The mux pin is short for multiplexing and you don't need it and it doesn't appear to be hooked up anyway.

The Sense pins are for phase current control and u can probably just leave those unconnected.

It wouldn't be too complex to control it with transistors, but the chip would be much easier if you can manage giving it access to a serial port. Here's a good link with circuit examples. http://www.eio.com/jasstep.htm (http://www.eio.com/jasstep.htm)
Title: Re: IC pin help
Post by: ed1380 on February 17, 2008, 10:12:59 PM
haha. i was looking at that page earlier today.
about this.
Quote
When making connections to either a PC parallel port, or I/O pins of a microcontroller, be sure to isolate the motor well. High voltage spikes of several hundered volts are possible as back EMF from stepper motor coils. Always use clamping diodes to short these spikes back to the motor's power bus. The use of optical isolation devices (optoisolators) will add yet another layer or protection between the delicate control logic and the high-voltage potentials which may be present in the power output stage. Whenever possible, use separate power supplies for the motor and the translator / microcontroller. This further reduces the chance of destructive voltages reaching the controller, and reduces or eliminates power supply noise that may be introduced by the motor.
will the darlington array provide enough coverage?

also that page doesnt give any definite help for using a serial port.
since digital electronics and software are my weak point, I'm clueless on how serial communication works. I've heard of people using parallel ports to drive steppers. would that still be possible with the said IC in first post?
Title: Re: IC pin help
Post by: ed1380 on February 28, 2008, 12:11:24 AM
thanks for the help  ::)

I'm about to make this. (see pic)

am i forgetting any resistors, diodes, etc?

and i got a question. datasheet says maximum imput and supply voltage 7v. maximum output  60v. how does that happen?
Title: Re: IC pin help
Post by: ed1380 on February 28, 2008, 03:11:17 PM
cmon does no one ever see my threads. I'm about to start soldering.
Title: Re: verify scematic plz
Post by: paulstreats on February 28, 2008, 05:59:59 PM
what chip is it that you are using?
Title: Re: verify scematic plz
Post by: ed1380 on February 28, 2008, 06:00:15 PM
atmega8
i found this http://reprap.org/bin/view/Main/StepperDriverWithUDN2559
it's the same thing i did except for the 12v going to K. but i did that too and still doesnt work. stupid darlington aray only outputs low even when datasheet says bipolar output
Title: Re: verify scematic plz
Post by: Admin on March 15, 2008, 04:49:57 PM
sorry for the late reply . . .

I noticed that you are running regulated power to a stepper motor . . . probably the problem . . .