LM3411AM5-3.3/NOPB

Overview

The LM3411AM5-3.3/NOPB is a precision secondary regulator and driver manufactured by Texas Instruments, designed specifically for driving optoisolators to provide feedback in isolated power supply applications. This fixed-voltage device outputs 3.3 V with an initial accuracy of ±0.5%. It operates within a temperature range of -40°C to 85°C and features a low operating supply current of 85 µA. The component is housed in a surface-mount SC-74A (SOT-753) package, ensuring compact integration into modern electronic designs requiring high-precision voltage referencing.

Feature Summary

• Precision shunt regulation optimized for optoisolator driving
• Fixed 3.3 V output with ±0.5% initial accuracy
• Low-power operation suitable for energy-efficient systems

Applications

• Flyback converter feedback loops
• Isolated DC-DC converter control circuits
• Switching power supply secondary side regulation

Procurement Notes

Verify the complete part number including the suffix NOPB to confirm lead-free compliance and specific tape-and-reel packaging configuration. Ensure the SC-74A footprint matches the design layout. Confirm the 3.3 V variant is selected, as other voltage options exist within the same family. Cross-reference the manufacturer's latest datasheet revision to ensure compatibility with current manufacturing standards.

Selection Notes

Select this component when a dedicated secondary-side regulator for optocoupler drive is required rather than a general-purpose reference. The fixed 3.3 V output eliminates external resistor networks, simplifying the circuit design. Consider the low quiescent current for battery-operated or efficiency-critical applications. Verify that the thermal performance in the SOT-753 package meets the system's dissipation requirements under maximum load conditions.

Part Context

This device belongs to the LM3411 series of precision secondary regulators from Texas Instruments. The series includes variants for both 3.3 V and 5 V outputs, catering to common logic levels in isolated power supplies. The LM3411 family is distinct from standard bandgap references as it integrates the driver stage necessary for direct optoisolator interfacing, reducing component count in flyback and forward converter topologies.

Replacement Considerations

The LM3411AM5X-3.3/NOPB is a reel-packaged version of the same functional device. Other LM3411 variants with different output voltages or packages may require circuit redesign due to pinout or electrical specification differences.