TheULN2003are high-voltage, high-current darlington drivers comprised of seven NPN arlington pairs. All units feature integral clamp diodes for switching inductive loads. Applications include relay, hammer, lamp and display (LED) drivers.
•Output Current (Single Output): 500mA (MAX.)
•High Sustaining Voltage Output: 50V (MIN.)
•Output Clamp Diodes
•Inputs Compatible With Various Types Of Logic
IF you want know more about ULN2003 please downloadULN2003 datasheet pdf.