LNK420EG

LED Drivers are essential elements of many lighting systems and have become the leading technology for energy efficiency, long lifetime and usage convenience. The LNK420EG is an integrated circuit that can provide the power required for most LED applications. It provides a very cost-effective solution by combining a high voltage buck converter, a low voltage step-down converter, and three constant-current regulation systems in a single integrated circuit. The LNK420EG offers superior performance and low power consumption to support the latest LED lighting designs.

Overview

The LNK420EG is a 6 A, 420 V, high-efficiency, low-EMI buck controller with integrated EMI filter and high voltage startup circuit. This buck controller supports an input voltage of up to 600 V and is designed for offline AC/DC conversion topology. The device features high-efficiency operation with a peak efficiency of 98.3% and a quiescent current of less than 45 uA. It also provides a configurable soft-start, over-current protection, under voltage lockout and Thermal Shutdown (TSD).

Features

• High efficiency: 98.3%
• Input Voltage: up to 600 V
• Output Voltage Range: 6 V – 60v
• Output Current: 6 A
• Reverse Current Protection
• Primary-Side Regulation (PSR)
• Constant Current Regulation (CCR)
• Soft-Start
• EMI Filter
• High-Voltage Startup Circuit
• Programmable Over-Current Protection
• Under Voltage Lockout
• Thermal Shutdown (TSD)

Applications

The LNK420EG is ideal for LED lighting applications such as outdoor lighting, directional lighting, accent lighting and more. The device can achieve a high efficiency while also providing excellent EMI suppression, low power consumption and a low startup delay. The LNK420EG is a cost-effective solution for LED lighting designs.

Working Principle

The LNK420EG uses a buck converter topology, which consists of an input voltage, an output voltage and a switch. The switch is used to control the flow of current from the input to the output. The device can operate at high frequencies, allowing for small inductors and capacitors in the design. A pulse width modulated (PWM) signal is used to control the switch, which will in turn control the output voltage. The device can also include secondary-side regulation, which monitors the output voltage and helps to keep it within an acceptable range.

The LNK420EG also includes a primary-side regulation (PSR) mechanism, which can be used to regulate the current. The PSR circuitry samples the voltage across the inductor and adjusts the output voltage accordingly. This can be used to help reduce ripple and provide a more stable output voltage.

The device also includes over-current protection (OCP) and thermal shut-down protection (TSD). The OCP module monitors the current through the switch and will shut off the device when a fault current is detected. The TSD module monitors the temperature of the device and will shut it off if it exceeds the thermal shutdown temperature.

Conclusion

The LNK420EG is an integrated circuit designed for offline AC/DC conversion topology that offers a very cost-effective solution for LED lighting designs. The device features high efficiency and excellent EMI suppression, with a peak efficiency of 98.3%. It also provides programmable over-current protection, high-voltage startup circuit and Thermal Shut-down protection. The LNK420EG is an ideal solution for high-efficiency LED applications such as outdoor lighting, directional lighting and accent lighting.