The ULN2003 datasheet specifies that it is a high-voltage high-current Darlington transistor array.
Each consists of seven NPN Darlington pairs that feature high-voltage outputs with common-cathode clamp diodes for switching inductive loads. The collector-current rating of a single Darlington pair is 500 mA.
The Darlington pairs can be paralleled for higher current capability. Applications include relay drivers, hammer drivers, lamp drivers, display drivers (
LED and gas discharge), line drivers, and logic buffers.