ULN2003AD Darlington Transistors by HTC Korea – 7-Channel Relay Driver for Industrial & Consumer Systems
The Darlington Transistors ULN2003AD by HTC Korea are high-voltage, high-current relay drivers designed to control inductive loads such as relays, solenoids, motors, and LEDs. This 7-channel driver IC is built with Darlington Transistors to provide high current gain and fast switching, making it a go-to solution in automotive, home appliances, and industrial control systems.
In this blog, we’ll explore the specifications, features, applications, wiring setup, and cross-manufacturer options from Texas Instruments. Whether you're building a relay board or upgrading an automation controller, the ULN2003AD offers a compact and efficient solution in the Discrete Semiconductors family.
Technical Specifications of ULN2003AD
-
Manufacturer: HTC Korea
-
Part Number: ULN2003AD
-
Type: Darlington Transistor Array
-
Channels: 7 Independent Channels
-
Output Voltage: 50V max
-
Output Current (Each Channel): 500mA continuous
-
Input Compatibility: TTL, CMOS Logic
-
Clamp Diodes: Internal Freewheeling Diodes for Inductive Load Protection
-
Package Type: 16-pin SOIC
-
Category: Semiconductors, Discrete Semiconductors, Transistors, Darlington Transistors
Compact, integrated, and versatile—ULN2003AD is ideal for high-current control in modern logic-driven systems.
Key Features of ULN2003AD Darlington Transistors
-
7-Channel High-Current Output – Drive up to 500mA per channel
-
Integrated Clamp Diodes – Built-in flyback protection for inductive loads
-
Logic-Level Compatible Inputs – Interfaces easily with microcontrollers and logic ICs
-
High Voltage Tolerance – Supports output voltages up to 50V
-
Space-Saving Package – Compact SOIC-16 form factor suitable for dense PCB layouts
The ULN2003AD Darlington Transistors simplify relay and motor control in embedded electronics, making them a staple among power interface Transistors.
Applications of ULN2003AD
The ULN2003AD Darlington Transistors are commonly used in:
-
Relay Driver Boards
-
Stepper Motor Control Systems
-
Home Automation & Smart Appliances
-
Industrial Control Units
-
LED and Lamp Drivers
-
Printer & Scanner Mechanisms
As part of the Semiconductors family, this IC offers reliable high-power switching with minimal external circuitry.
Wiring and Pin Configuration Overview
Typical Connection Guide:
-
Pins 1–7: Inputs from microcontroller or logic circuit
-
Pins 10–16: Outputs to loads (e.g., relays, motors)
-
Pin 8 (GND): Connect to ground
-
Pin 9 (COM): Common flyback diode connection to power supply
This setup ensures seamless operation of the Darlington Transistors, especially in inductive load conditions.
Use Case Scenario: Relay Board for Automation Panel
Scenario: An industrial automation integrator needed a 7-relay control board to manage multiple field devices using a microcontroller.
Problem: Using discrete Transistors increased PCB space and added complexity for flyback protection.
Solution: The ULN2003AD Darlington Transistors provided a single-chip solution with built-in clamping diodes and reliable switching capacity.
Result: Reduced component count, improved reliability, and faster assembly — all while leveraging efficient Discrete Semiconductors.
Also Available from Other Manufacturers
If you're looking for alternatives to the ULN2003AD, consider options from:
These cross-compatible parts are also available at Xon Electronics for design flexibility.
Download Datasheet for ULN2003AD
Need detailed performance graphs, pinouts, or input/output characteristics?
[Download the ULN2003AD Datasheet from Xon Electronics]
Why Buy from Xon Electronics?
Order ULN2003AD Darlington Transistors by HTC Korea from Xon Electronics and benefit from:
- Genuine HTC Korea Components
- Global Shipping – USA, India, Australia, Europe & more
- OEM & Bulk Pricing
- Application Support from Our Engineering Team
- Secure and Fast Online Ordering
Your one-stop source for reliable Semiconductors, Transistors, and Discrete Semiconductors.
FAQs – ULN2003AD Darlington Transistors
Q1. How many channels are in the ULN2003AD?
It features 7 independent Darlington driver channels.
Q2. Can this IC drive relays directly?
Yes, each channel can drive up to 500mA and includes flyback diodes.
Q3. Is this compatible with 5V logic?
Yes, it works with TTL and CMOS logic levels.
Q4. Does it need external diodes for inductive loads?
No, integrated clamp diodes are built-in for each output.
Q5. Is global shipping available?
Yes, Xon Electronics ships worldwide including USA, India, Australia, Europe, and other countries.
Conclusion
The ULN2003AD Darlington Transistors by HTC Korea offer an efficient, compact, and reliable solution for driving relays, motors, and lamps. Built for seamless integration with logic-level circuits, this IC streamlines power interface design across industrial and consumer electronics.
Available now at Xon Electronics — shipping globally to USA, India, Australia, Europe, and beyond.