LM5109AMAX/NOPB

Overview

The LM5109AMAX/NOPB is a high-voltage, cost-effective half-bridge gate driver designed to drive both high-side and low-side N-channel MOSFETs in synchronous buck or half-bridge configurations. It features independent TTL-compatible inputs for robust control. The device supports bootstrap supply voltages up to 108V DC and delivers a 1A peak output current with 1.0A source and sink capability. Typical propagation times are 30 ns, with rise and fall times of 15 ns driving a 1000 pF load. Excellent propagation delay matching is achieved at 2 ns typical. Under-voltage lockout is provided on both power rails.

Feature Summary

• Drives both high-side and low-side N-channel MOSFETs
• Independent TTL compatible input thresholds
• Bootstrap supply voltage support up to 108V DC
• Under-voltage lockout on both low-side and high-side power rails

Applications

• Current fed push-pull converters
• Half and full bridge power converters
• Solid state motor drives
• Two switch forward power converters

Procurement Notes

Verify the specific suffix 'MAX' indicates the SOIC-8 package variant when sourcing. Confirm RoHS compliance status via the manufacturer's official documentation, as historical data may vary by production batch. Ensure the component matches the National Semiconductor (now Texas Instruments) datasheet specifications for electrical parameters before integration into designs requiring high-voltage isolation.

Selection Notes

Select this component for applications requiring isolated gate driving in high-voltage environments up to 90V rail voltages. The independent TTL inputs simplify logic interfacing without additional level shifting circuitry. Consider the thermal performance of the SOIC-8 package for heat dissipation requirements in dense PCB layouts compared to thermally enhanced alternatives.

Part Context

This part belongs to the LM5109 series of high-voltage gate drivers. It is pin-compatible with the ISL6700, facilitating direct upgrades or replacements in existing designs. The series is characterized by its ability to operate with floating high-side drivers and robust level shift technology for clean signal transitions.

Replacement Considerations

The LM5109A is explicitly noted as pin-compatible with the ISL6700. Other variants within the LM5109 family, such as those with different package suffixes (e.g., WSON), may offer thermal advantages but require layout adjustments.