Driving steppers with ULN2803

[izua]

uln2803 hot

I'm making a stepper driver with ULN2803. It's working, but the IC heats up very quickly. I'm not using microstepping. I'm using two outputs paralleld together, totaling one ULN IC per driver (8 outputs / 2 = 4 outputs, as needed for uniploar driving).

Is it safe to operate the ULN in high temps?Or should I get some cooling? Is there cooling for DIP packages?

 

[H_u_n_t_e_r]

ic uln2803 php

You should limit the current or decrease the supply voltage

 

[plusminus]

uln2803 heat

There are heatsinks for DIP.
See Fischer ( **broken link removed** ) or Aavid
Take for example a look at Farnell: art# 4620896

But you have to calculate what is safe. Calculate the thermal resistance of the heatsink to get the ic below breakdown temperature.

 

[TLL]

Hi

No it is not safe to operate at high temperatures.....
Also u soulh use heat sink...probably u`r motor has high amp(ic has
500 mA)....and that is why
the ic get hot.I attach pdf for ic maybe it helps.