Abdul Mujid:

When doing any design is it highly advisable to access all the part data sheets and become familiar with the parts and their capabilities.

A quick Google search will reveal one copy of the '2803 data sheet at http://www.ozitronics.com/data/uln2803.pdf

Opening that up to the first page will reveal...



Do note that when using these drivers that is is necessary to observe the total package current ratings and total package power dissipation. You cannot expect all 8 outputs to sink full rated current in a continuous manner at the same time.

Michael Karas