LK115D33

Overview

The LK115D33 is a fixed-output low dropout linear voltage regulator from STMicroelectronics, providing a nominal 3.3 V output with ±3% tolerance at 25 °C. It supports up to 100 mA load current within an operating input voltage range of 4.3 V to 20 V. The device features very low quiescent current (280 µA typical in ON mode) and extremely low standby consumption (0.01 µA). It includes dual logic-controlled electronic shutdowns for power management, internal current and thermal limiting protection, and requires only a 2.2 µF output capacitor for stability.

Feature Summary

• Dual active HIGH and active LOW shutdown logic control enables precise board-level power management and standby modes.
• Very low dropout voltage ensures efficient operation in battery-powered systems with minimal voltage loss.
• Integrated current and thermal limit protection safeguards the device against overload conditions.
• Requires minimal external capacitance (2.2 µF) for stability, reducing component count and board space.

Applications

• Battery-powered portable electronics
• Low noise analog circuit supply regulation
• Embedded system local voltage regulation
• General purpose linear voltage regulation

Procurement Notes

Verify the specific ordering suffix matches the required packaging configuration, as standard availability may vary by region. Confirm that the SO-8 package dimensions align with the target PCB footprint requirements. Ensure the design accounts for the specified minimum output capacitance value to maintain loop stability under all load conditions.

Selection Notes

Select this regulator when a stable 3.3 V rail is required with minimal quiescent current draw. The dual shutdown inputs offer flexibility for system power sequencing compared to single-enable alternatives. Verify that the input voltage remains within the 20 V absolute maximum rating during transient events.

Part Context

This component belongs to the LK115XX series of very low drop regulators manufactured by STMicroelectronics. The series includes variants with different fixed output voltages, such as 3.0 V and 5.0 V, sharing identical pinouts and protection features. These devices are designed for applications prioritizing low power consumption and high efficiency in compact form factors.

Replacement Considerations

LK115D30-TR

FAQ

How does the LK115D33 handle shutdown states?

It features two logic-controlled electronic shutdown pins (active HIGH and active LOW), allowing flexible control to reduce total power consumption in standby modes.

What is the minimum output capacitance required for stability?

The device requires a minimum output bypass capacitance of 2.2 µF with an ESR between 0.5 Ω and 10 Ω for stable operation.