LK112M18TR

Overview

The LK112M18TR is a fixed-output low-dropout linear regulator manufactured by STMicroelectronics, providing a stable 1.8 V output with a maximum current capacity of 150 mA to 200 mA. It operates within an input voltage range of 2.5 V to 14 V and features a typical dropout voltage of 500 mV at full load. The device incorporates shutdown functionality controlled by TTL or CMOS logic levels, reducing quiescent current to 100 nA in OFF mode. Key electrical specifications include a static current of 250 µA in ON mode, line regulation of 40 mV, load regulation of 90 mV, and voltage accuracy of ±2%. It is housed in a SOT-23-5 package.

Feature Summary

• Integrated shutdown control via logic-level pin for power management
• Internal thermal and overcurrent protection circuits
• Low noise performance suitable for sensitive analog loads

Applications

• Battery-powered portable electronics
• Embedded systems requiring stable low-voltage rails
• Noise-sensitive sensor power supplies

Procurement Notes

Verify the specific suffix (M vs SM) against the manufacturer datasheet to confirm exact output current ratings, as variations exist between 150 mA and 200 mA variants. Ensure the ordering code matches the required packaging format, such as cut tape or reel, for production compatibility. Confirm RoHS compliance status and moisture sensitivity level requirements prior to procurement.

Selection Notes

Select this component when a fixed 1.8 V rail is required with moderate current demands up to 200 mA. The SOT-23-5 package suits space-constrained designs. Consider the 500 mV dropout voltage relative to the minimum input supply; ensure the input voltage remains sufficiently above 1.8 V + 0.5 V under all operating conditions to maintain regulation.

Part Context

This part belongs to the LK112S family of low-noise, low-dropout regulators featuring shutdown capabilities. The series utilizes an internal PNP pass transistor to achieve low dropout characteristics. The family supports various fixed output voltages and includes noise bypass pins for further filtering, targeting applications where power efficiency and signal integrity are critical.

Replacement Considerations

Cross-reference with other LK112S variants (e.g., LK112SM18TR) to verify if the higher 200 mA rating is necessary. Check for equivalent LDOs from other manufacturers offering similar 1.8 V outputs, SOT-23-5 packages, and shutdown pins, ensuring pinout compatibility.