L7983PU33R

Voltage Regulators - DC DC Switching Regulators Overview

The L7983PU33R is a synchronous step-down switching regulator from STMicroelectronics, designed to deliver up to 300 mA DC output current. It operates with an input voltage range of 3.5 V to 60 V and provides a fixed 3.3 V output. The device features a peak current mode architecture with dynamic selection between Low Consumption Mode (LCM) and Low Noise Mode (LNM). Key electrical specifications include a typical quiescent current of 10 µA in LCM when VIN exceeds 24 V, a shutdown current of 2.3 µA, and a programmable switching frequency ranging from 200 kHz to 2.2 MHz. It supports optional spread spectrum dithering and external clock synchronization.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Dynamic transition capability between Low Consumption Mode for light-load efficiency and Low Noise Mode for constant switching frequency operation.
• Integrated internal compensation network and soft-start mechanism simplifying design and reducing component count.
• Comprehensive protection suite including pulse-by-pulse current limiting, overvoltage protection, thermal shutdown, and adjustable UVLO threshold.
• Open-collector RST output enabling precise output voltage sequencing for digital loads such as microcontrollers and FPGAs.

Voltage Regulators - DC DC Switching Regulators Applications

• Power supply stages for industrial bus standards including 12 V, 24 V, and 48 V systems.
• Voltage regulation for embedded digital loads like microcontrollers and FPGAs requiring clean power.
• Compact DC/DC converter designs in space-constrained applications utilizing high switching frequencies.

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the specific suffix PU33R confirms the fixed 3.3 V output variant and DFN package configuration. Ensure compatibility with required operating temperature ranges and check for RoHS compliance status via official datasheets before integration. Confirm pinout alignment with target PCB layout to avoid functional mismatches during assembly.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a wide input voltage range up to 60 V is required alongside moderate output current capabilities. It is suitable for designs prioritizing low standby power through LCM or low EMI through LNM. Consider the programmable frequency range if synchronization with other system clocks is necessary. Evaluate thermal performance based on expected load conditions and ambient temperatures.

Voltage Regulators - DC DC Switching Regulators Part Context

The L7983PU33R belongs to the L7983 family of synchronous buck converters. This series is engineered for industrial applications demanding high efficiency and noise control. The device integrates advanced features like dynamic mode switching and internal compensation, distinguishing it from basic regulators by offering flexible operational modes tailored to specific load profiles and electromagnetic interference constraints.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct substitutes within the same family include variants with different fixed output voltages such as 5 V, or adjustable versions. Cross-family replacements must match the 60 V input rating, 300 mA current capacity, and DFN-10 package dimensions. Verify that alternative devices support similar quiescent current levels and switching frequency ranges to maintain system performance.

Voltage Regulators - DC DC Switching Regulators FAQ

How does the L7983PU33R manage noise versus efficiency?

It allows dynamic selection between Low Consumption Mode (LCM), which maximizes efficiency at light loads, and Low Noise Mode (LNM), which maintains a constant switching frequency to minimize electromagnetic interference.

What protection features are integrated into the L7983PU33R?

The device includes internal current limiting, overvoltage protection, thermal shutdown, and an adjustable under-voltage lockout (UVLO) threshold to ensure safe operation under various fault conditions.