LM3404MRX

Overview

The LM3404MRX is a constant current buck regulator designed for driving high-power LEDs. It operates with an input voltage range of 6 V to 42 V and delivers a fixed output current of 1.0 A. The device supports PWM dimming control and functions within a switching frequency range of 10 kHz to 1 MHz. It features a maximum output voltage of 40 V and includes internal protection mechanisms. The component is housed in an 8-pin HSOIC (DDA) package and is rated for operation between -40°C and +125°C junction temperature.

Feature Summary

• Provides precise constant current regulation for high-power LED loads
• Supports external PWM dimming control for brightness adjustment
• Integrates an internal power switch for simplified circuit design
• Includes thermal shutdown and undervoltage lockout protections

Applications

• Automotive exterior lighting systems
• General illumination LED drivers
• Portable lighting devices
• Industrial LED backlighting

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to ensure correct packaging and tape-and-reel specifications. Confirm that the requested part number matches the exact electrical parameters and package type required for the target application. Cross-reference the datasheet revision date to ensure compatibility with current design standards. Ensure compliance with RoHS directives if environmental regulations apply to the end product.

Selection Notes

Select this component when a fixed 1.0 A drive current is required for high-power LED arrays. The wide input voltage range allows flexibility in power supply design, accommodating various battery or bus voltages. Consider the operating temperature range and thermal management requirements for the intended environment. Evaluate the need for PWM dimming capabilities versus analog methods to determine if this controller meets system control objectives.

Part Context

The LM3404MRX belongs to the LM3404 family of LED drivers from Texas Instruments. It is specifically engineered as a buck regulator topology suitable for step-down voltage conversion while maintaining constant current. The device is often compared with variants like the LM3404HVMAX for higher voltage applications. It serves as a core component in efficient LED lighting solutions requiring robust current regulation.

Replacement Considerations

Direct substitutes include the LM3404MR/NOPB and LM3404MREVAL for evaluation purposes. Verify pin compatibility and electrical specifications before swapping with other LED driver ICs. Ensure that any alternative component supports the same 1.0 A output current and buck topology requirements.