LM27951SDX

Overview

The LM27951SDX/NOPB is a white LED adaptive switched-capacitor current driver manufactured by Texas Instruments. It features an input voltage range of 2.8V to 5.5V and supports up to four output channels, each capable of delivering 30mA. The device utilizes a 14-WSON (4x3) package with exposed pad for thermal management. Operating temperatures range from -40°C to +85°C. Key electrical parameters include a switching frequency of 750kHz and output voltage regulation between 2.5V and 3.9V. The component integrates internal switches and supports direct PWM dimming for backlight applications.

Feature Summary

• Adaptive 1.5X/1X switched-capacitor topology for efficient white LED driving
• Direct PWM dimming capability for precise brightness control
• Integrated internal switches eliminate external inductor requirements
• Supports up to four independent LED channels with 30mA per channel

Applications

• Backlight drivers for mobile devices
• White LED lighting systems
• Portable electronic display illumination
• Battery-powered LED arrays

Procurement Notes

Verify the complete part number including the suffix NOPB when ordering, as it indicates lead-free status and RoHS compliance. Confirm the package variant matches the required footprint, specifically the 14-WSON (4x3) configuration. Ensure that the design accounts for the thermal performance associated with the exposed pad layout. Cross-reference the latest datasheet revision to confirm any updates to electrical characteristics or recommended operating conditions before finalizing procurement specifications.

Selection Notes

Select this component for applications requiring compact size and high efficiency without magnetic components. The fixed 30mA output current suits standard white LED strings. Consider the 2.8V minimum input voltage for battery-operated systems. The integrated PWM dimming interface simplifies control logic. Evaluate the thermal dissipation capabilities of the WSON package against the expected ambient temperature and power density constraints of the target enclosure design.

Part Context

The LM27951 belongs to Texas Instruments' family of switched-capacitor LED drivers. It complements other PMIC solutions by providing a specialized topology for white LEDs where inductors are undesirable. The device shares functional similarities with other TI LED controllers but distinguishes itself through its adaptive capacitor switching architecture. It serves as a dedicated solution for multi-channel backlighting in space-constrained portable electronics.

Replacement Considerations

Public documentation identifies LM27951SD/NOPB as a related variant. Verify pinout compatibility and electrical equivalence before substitution. No other specific substitute part numbers are confirmed in public sources.