problem with ULN2003

[alchalaby]

hi I tray to drive stepper motore using PIC and my problem now that the uln2003 ic not work propably . I connect its PIN8 to GND and PIN12 TO +12 V but when I put the 5V in the input pin i get only 0.6 v in the out put pin !!!!??? your help please

 

[3lectrokid]

what stepper are you using?
is it bipolar or unipolar?
what is its amp rating?
is the PIC outputing voltage?

more details are essential

 

[ronsimpson]

Gnd pin to Gnd. OK
Diode pin to +12 volts, (pin12???)
The ULU2003 only pulls down. It will not pull up.
Input=5V then output will = about 0 volts.

 

[alchalaby]

Rated voltage ： 5VDC
Number of Pole ： 4
Speed Variation Ratio ： 1/64
Stride Angle ： 5.625° /64
DC resistance ： 200Ω±7%(25℃)
Idle In-traction ： Frequency >600Hz
Idle Out-traction ： Frequency >1000Hz
In-traction Torque >34.3mN.m(120Hz)
Self-positioning Tor >34.3mN.m
insulated resistance >10MΩ(500V)
insulated electricity power ：600VAC/1mA/1s
Insulation grade ：A
Rise in Temperature <40K(120Hz)
Noise <40dB(120Hz,No load,10cm)

 

[be80be]

ULN2003 sink power not sources power

 

[3lectrokid]

pin 12 is an output to driver #6
The clamp pin is pin 9 not 12

 

[alchalaby]

soory not pin 12 pin 9 connectedto 12 v

 

[3lectrokid]

how many pins does the Stepper have. This is key to know if it is bipolar or unipolar. I am guessing by 4 poles it has 5 pins in which case it would be a unipolar?

 

[alchalaby]

yes its five pins

 

[alchalaby]

dear be80be my stteper work on 5 v not 12 v

 

[3lectrokid]

if it is unipolar you connect the common to the 12v source that also connects to pin9(clamp). the outputs of the stepper goes to pins 16-12(outputs 1,2,3,4 respectivly). the inputs go to pins 1-4(1,2,3,4 respectivly). Pin 8 goes to ground

 

[3lectrokid]

I also just noticed your using 12v on a stepper that only allows 5V. make sure you use the stepper inside of its rated voltage (<=5v)

 

[alchalaby]

how can i connect the commone ot testepper to 12 v

 

[3lectrokid]

this will help **broken link removed**

 

[alchalaby]

i connect it as you mention but still the stepper not work . may the uln damage by the 12 v i connect previously ?

 

[alchalaby]

i think the problem in the uln2003 cous i check its output pin giv 0.6 voltage only

 

[ronsimpson]

If the stepper is burned up because of 12 volts then the ULN2003's output will be 0 volts only. With a meter check if there is resistance in the stepper.

 

[be80be]

alchalaby 5 volts 12volts that really don't matter the way your talking your trying to power with the ULN2003 not going to happen

It can only sink power **broken link removed**

 

[bryan1]

I don't think running a 5 volt stepper on 12 volts will do any harm, the steppers on my cnc are rated at 2.3 volt and I run them at 30 volts....... Also 5 and 6 wire unipolar steppers can be run as bipolar by simply leaving the centretap (voltage wire/s) unconnected. I have also tested this with my 6 wire steppers and found they are more powerful running on bipolar.