LDK715PU42R

Overview

The LDK715PU42R is a fixed-output linear voltage regulator from the STMicroelectronics LDK715 series, providing a stable 4.2 V output with a maximum current of 85 mA. It operates within an input voltage range of 4.3 V to 24 V and features a typical dropout voltage of 500 mV at full load. The device maintains an ultra-low quiescent current of 5 μA under full load conditions. It includes internal protection mechanisms such as short-circuit current limiting and thermal shutdown. The component is housed in an 8-lead DFN 3x3 mm package and supports operation across a temperature range of -40 °C to +125 °C.

Feature Summary

• Ultra-low quiescent current of 5 μA at full load for battery-powered efficiency
• High input voltage capability ranging from 4.3 V to 24 V
• Compatible with small ceramic output capacitors (0.47 μF to 10 μF)
• Integrated fault protection including short-circuit current limitation

Applications

• Low power industrial applications requiring wide input voltage ranges
• Battery-powered systems prioritizing extended operational life
• Portable electronic devices utilizing low-dropout regulation
• General-purpose low noise power supply circuits

Procurement Notes

Verify the specific output voltage configuration during procurement, as the LDK715 series offers multiple fixed options including 3.3 V, 4.2 V, and 5.0 V. Confirm that the ordering suffix corresponds to the required 4.2 V variant. Ensure compatibility with the 8-QFN 3x3 mm package footprint for PCB layout. Check RoHS compliance status if restricted substances are a project constraint.

Selection Notes

Select this component when a high input voltage range up to 24 V is required alongside minimal standby power consumption. The 4.2 V fixed output is suitable for specific rail requirements where standard 3.3 V or 5 V rails are insufficient. Consider the 85 mA output limit against peak load demands. The DFN8 package is appropriate for space-constrained designs requiring surface mount assembly.

Part Context

The LDK715PU42R belongs to the LDK715 family of high-voltage, low-quiescent-current LDO regulators manufactured by STMicroelectronics. This series is designed to replace older linear regulators in applications demanding lower power dissipation and wider input voltage tolerance. The family shares common architectural features but varies by output voltage and package type, specifically offering SOT23-5 and DFN8 configurations.

Replacement Considerations

Direct substitutes include other LDK715 variants with different fixed output voltages, such as LDK715PU33R (3.3 V) or LDK715PU50R (5.0 V), provided the system voltage requirement changes. Cross-family replacements may require verification of pin compatibility and thermal performance characteristics.