LP2975AIMM-3.3

Overview

The LP2975AIMM-3.3 is a MOSFET LDO Driver/Controller manufactured by Texas Instruments, designed to facilitate high-current low-dropout regulator designs using an external P-channel FET. It features a precision output voltage with a 1.5% accuracy grade and operates within a wide supply voltage range of 1.8V to 24V. The device includes a low-power shutdown input drawing less than 1 µA, a typical operating current of 180 µA at 5V, and built-in overtemperature protection. It supports standard 3.3V outputs or adjustable configurations via external dividers.

Feature Summary

• Ultra-small VSSOP-8 package design
• High open loop gain for excellent regulation
• User-selectable dropout voltage via external FET sizing
• Integrated current limit amplifier

Applications

• High-current 5V to 3.3V Regulator
• Post Regulator for Switching Converter
• Current-limited Switch

Procurement Notes

Verify the specific suffix 'AIMM' corresponds to the A-grade 1.5% accuracy requirement and the MM VSSOP-8 package variant. Confirm that the internal RSET value matches the 3.3V configuration (typically 39.9k) if fixed output is required without external programming resistors. Ensure the external P-FET selection aligns with the controller's gate drive capabilities and thermal requirements.

Selection Notes

Select this component when designing custom high-current linear regulators requiring precise voltage control and minimal quiescent current consumption. The A-grade specification ensures tighter output voltage tolerance compared to standard grades. Consider the external P-FET's on-resistance and gate threshold voltage carefully, as these directly impact the overall dropout voltage and efficiency of the final power supply design.

Part Context

This part belongs to the LP2975 family of MOSFET LDO controllers from Texas Instruments. The family allows designers to build flexible linear regulators by pairing the controller with various external P-channel MOSFETs. Variants in the series include different output voltage trims and temperature grades, providing options for diverse industrial and consumer electronics applications requiring robust power management solutions.

Replacement Considerations

LP2975IMM-3.3/NOPB

FAQ

How is the output voltage determined for the LP2975AIMM-3.3?

The LP2975AIMM-3.3 provides a standard 3.3V output voltage. This is achieved through an internal trimmed bandgap reference and a specific internal resistor setting (RSET) optimized for the 3.3V configuration.

What is the function of the ON/OFF pin?

The ON/OFF pin controls the device state. Applying a voltage above the threshold turns the regulator on, while pulling it below the threshold activates the low-power shutdown mode, reducing quiescent current to less than 1 µA.