Darlington Array: The ULN2003 is a Darlington transistor array, which means it contains several Darlington pairs (pairs of transistors) in a single package. Each Darlington pair consists of two bipolar transistors, providing a high level of current gain (amplification).
Number of Outputs: The ULN2003 typically comes in a package with seven Darlington pairs, allowing you to control up to seven separate loads independently.
Input and Output Pins: The IC has a set of input pins for connecting to your microcontroller or digital logic circuit. Each output is connected to the collector of a Darlington pair, making it capable of sinking a relatively high current.
Diode Protection: Each Darlington pair has a built-in freewheeling diode (flyback diode) to protect against inductive kickback voltage when driving inductive loads like relays or motors.
Applications: The ULN2003 is commonly used in applications where there's a need to control multiple high-current loads using microcontrollers or digital logic. Some typical applications include driving stepper motors, controlling relays in automation and robotics projects, and powering LED arrays.
Voltage Ratings: The ULN2003 is often available in various voltage ratings, such as ULN2003A (typically rated for 50V outputs) and ULN2003V12 (rated for 12V outputs). Make sure to select the appropriate version for your application.
Datasheet: To use the ULN2003 effectively in your circuit, it's important to consult the datasheet provided by the manufacturer. The datasheet contains detailed information about pin configurations, electrical characteristics, recommended operating conditions, and application examples.
