LM3670MF-3.3

Voltage Regulators - DC DC Switching Regulators Overview

The LM3670MF-3.3 is a miniature step-down DC-DC converter manufactured by National Semiconductor, designed for ultra-low voltage circuits. It operates with an input voltage range of 2.5 V to 5.5 V and provides a fixed output voltage of 3.3 V. The device utilizes pulse width modulation control and features automatic PFM/PWM mode switching for efficiency optimization. Packaged in a 5-pin SOT-23 (LSSOP/TSOP5/6) format, it supports operation up to 85 °C.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Automatic transition between Pulse Frequency Modulation and Pulse Width Modulation modes
• Voltage-mode control architecture for stable regulation
• Compact SOT-23-5 package suitable for space-constrained designs

Voltage Regulators - DC DC Switching Regulators Applications

• Ultra-low voltage circuit power management
• Portable electronic devices requiring compact regulators
• Battery-powered systems needing efficient step-down conversion

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify RoHS compliance status as the component is listed as non-compliant in some databases. Confirm the manufacturer origin, noting that Texas Instruments acquired National Semiconductor's portfolio. Ensure the specific suffix matches the required output voltage and package variant before ordering.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 3.3 V output is required from a single-cell lithium or alkaline battery source. The automatic mode switching makes it suitable for applications with varying load currents where efficiency across light and heavy loads is critical. Ensure the input voltage remains within the 2.5 V to 5.5 V operational window.

Voltage Regulators - DC DC Switching Regulators Part Context

This part belongs to the LM3670 family of miniature step-down converters. It shares architectural similarities with the LM3671 and LM3674 series but offers a fixed 3.3 V output configuration. The device represents National Semiconductor's solution for low-voltage, high-efficiency power management in portable electronics prior to the company's acquisition by Texas Instruments.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

LM3670MF-1.2 and LM3670MF-1.8 are functionally similar variants within the same family but provide different fixed output voltages. Direct substitution requires verifying that the system design can accommodate the alternative output voltage level.