ULN2003APW

Introduction

ULN2003APW is an integrated circuit that consists of an array of seven NPN Darlington transistors with a common emitter connection linked to the input designed to drive low current loads. It is mostly used to drive inductive loads such as relays, solenoids, and stepper motors because of its high voltage and current ratings. This article will be discussing its application field and working principle.

Application Field

ULN2003APW is a popular choice for driving low current loads such as relays, solenoids, and stepper motors because of its high voltage (50V) and current (500mA per channel) ratings.It can also be used to drive more demanding loads such as lamps, heaters, and high power motors. It is mostly used in robotics, motion control applications, industrial automation, and home appliances.

Working Principle

ULN2003APW consists of seven NPN Darlington transistors which are connected in an array configuration. These transistors have a common emitter connection and a common emitter connection linked to the input. When input voltage is applied, the voltage creates a current through the base of the transistor. This current is amplified by the emitter-collector region of the transistor and regulated by a common emitter resistor. The amplified current is then passed to the load, providing the necessary voltage and current to drive the load. The current limiting diode provides protection from inductive spikes created by the inductive load.

Conclusion

In conclusion, ULN2003APW is a popular integrated circuit for driving low current loads such as relays, solenoids, and stepper motors because of its high voltage and current ratings. It is mainly used in robotics, motion control applications, industrial automation, and home appliances. The working principle of ULN2003APW is based on the amplification of the input voltage provided by a common emitter resistor and the current limiting diode provides protection from inductive spikes created by the inductive load.