LD3985G18R

Overview

The LD3985G18R is a fixed-output Low Dropout (LDO) voltage regulator manufactured by STMicroelectronics, providing a stable 1.8 V output with a maximum current capability of 0.15 A. It operates within an input voltage range of 2.5 V to 6 V and features an ultra-low dropout voltage, typically 0.06 V at full load. The device is housed in a 5-pin TSOT-23 package and includes logic-controlled shutdown functionality to minimize power consumption in standby modes.

Feature Summary

• Ultra-low dropout voltage performance for efficient battery-powered operation
• Logic-controlled electronic shutdown function to reduce total system power consumption
• Designed for stability with low ESR ceramic capacitors
• Internal protection against overcurrent and thermal overload

Applications

• Battery-powered wireless systems
• Mobile phones
• Low noise analog circuits requiring stable supply rails

Procurement Notes

Verify the specific suffix 'G18R' corresponds to the 1.8V fixed output variant in the official datasheet. Confirm the TSOT-23-5 pinout matches your PCB footprint design. Ensure compliance with RoHS standards if required for your manufacturing process.

Selection Notes

Select this component when a compact LDO with very low dropout is needed for 1.8V rails. It is suitable for applications where input voltage is close to the output level. Consider the 0.15A limit; higher current requirements may necessitate the LDS3985 series.

Part Context

This part belongs to the LD3985 family of BiCMOS voltage regulators known for low noise and low quiescent current. The G18R designation specifically identifies the 1.8V fixed output version packaged in TSOT-23, distinguishing it from other voltage options and packages within the same product line.

Replacement Considerations

For direct functional replacement, verify equivalent LDOs with 1.8V output, 150mA capacity, and TSOT-23 packaging. Cross-reference pinouts carefully as package variations exist within similar regulator families.