ON Semiconductor ULN2803: High-Voltage, High-Current Darlington Transistor Array

The ULN2803 from ON Semiconductor is a robust and versatile array of Darlington transistors designed to efficiently handle high-voltage and high-current loads in a wide range of applications. This integrated circuit (IC) is perfect for interfacing between low-level logic circuits and multiple peripheral power loads.

Key Features:

• Eight Darlington Pairs: Each ULN2803 chip contains eight NPN Darlington pairs that can handle a collective current of 500 mA per channel.
• High Voltage Outputs: The output voltage can sustain up to 50V, making it suitable for driving a variety of inductive loads such as relays, solenoids, and stepper motors.
• Integrated Suppression Diodes: Each channel includes a suppression diode for inductive loads, providing protection against voltage spikes during switching.
• Direct Interface to TTL or CMOS: The input compatible with TTL or 5V CMOS logic levels, allowing for direct connection to microcontrollers and other logic devices.
• High Current Capability: With the ability to handle 500 mA per channel, the ULN2803 can drive larger loads than many other similar ICs.

Applications:

The ULN2803 is ideally suited for use in a variety of applications, including:

• Relay Drivers
• Stepper and DC Brushed Motor Drivers
• LED Displays & LED Matrixes
• Line Drivers
• Logic Buffers

Technical Specifications:

Below are some of the technical specifications for the ULN2803:

• Output Current (single output): 500 mA max.
• Output Voltage: 50V max.
• Input Voltage: 3.5V to 5V (TTL/CMOS compatible)
• Package: DIP-18, SOIC-18

The ULN2803 from ON Semiconductor is a reliable solution for designers looking to drive high-current loads with low-level logic signals. Its built-in protection features and compatibility with various logic families make it a versatile choice for numerous applications.