LM3431AMHX/NOPB

LED Drivers are circuit components designed to control the flow of electricity in lighting systems, ensuring that the LED gets the right amount of power and protecting it from excessive current which can damage or ruin it. The LM3431AMHX/NOPB is a LED driver ideal for powering up to four strings of High Brightness LEDs (HB LED). It is a high efficiency, cost-effective, buck switching regulator that integrates four independent constant current sources.

Features

• High efficiency: Programmable frequency up to 1MHz
• High output current accuracy: ±3%
• Low quiescent current: 30μA @ no load
• Adaptive2X mode for highest efficiency
• High light output from smallest PCB area
• Uses only 16 external components
• Shutdown input for power saving mode

Applications

The LM3431AMHX/NOPB is a good choice for powering light-emitting diode (LED) applications including LCDs, cameras, PDAs, DRAM modules, mobile phone, handheld devices, and IR illuminators. It is especially suitable for driving long strings of LEDs in mobile phone display backlighting and camera flash lighting applications. Possibility of powering up to four strings of LEDs allows designers to create compact and thinner designs, with uniform light output.

Working Principle

The LM3431AMHX/NOPB is a synchronous buck regulator that uses control loop technology to deliver excellent accuracy and high efficiency. It uses a buck topology and a current sensing block to regulate the current flowing through the output capacitors. The device has two current sources, each of which has two independently controlled outputs. By using only two current sources and two outputs, the device achieves high efficiency, with current regulation that is accurate to ±3%.

The LM3431AMHX/NOPB also features a Shutdown input, which turns off the regulator, reducing the power consumption to an extremely low level (30μA max). This makes the device attractive for designs requiring a very low power consumption during standby.

In summary, the LM3431AMHX/NOPB is an ideal choice for applications requiring efficient current regulation, and low quiescent power consumption. Its wide input voltage range combined with its highly accurate current regulation makes it suitable for use in the most demanding applications.