LD59150PUR

Overview

The LD59150PUR is an industrial-grade, 1.5 A low-dropout linear regulator featuring a dual-supply architecture with VIN (0.8 V to 5.5 V) and VBIAS (2.7 V to 5.5 V). It provides an adjustable output voltage range of 0.8 V to 3.6 V with high accuracy (0.5% typical, 2% maximum). The device utilizes NMOS topology for ultra-low dropout voltage (65 mV typical at 1.5 A) and includes programmable soft-start, Power Good monitoring, current limiting, and thermal shutdown. It operates within a temperature range of -40 °C to +125 °C in a compact DFN10 (3x3 mm) package.

Feature Summary

• Dual supply pins allow independent control of input and bias voltages for optimized efficiency.
• Programmable soft-start circuit controls inrush current and enables safe power sequencing via the EN and PG pins.
• NMOS pass-element topology ensures minimal dropout voltage even under heavy loads and low input conditions.
• Integrated protection mechanisms include constant-current limiting and thermal shutdown to safeguard against overload.

Applications

• Automotive and industrial post-regulation
• Generic point-of-load (POL) conversion
• Supply for automotive and industrial ASICs and FPGAs
• Telecom infrastructure systems
• Advanced driver-assistance systems (A.D.A.S.)

Procurement Notes

Verify that the specific order code matches the required qualification grade. The LD59150PUR designation corresponds to the Industrial version, distinct from the Automotive-qualified LD59150PURY. Confirm package details and environmental compliance specifications prior to finalizing procurement orders to ensure alignment with system requirements.

Selection Notes

Select this component when a high-current LDO with independent bias control is necessary for noise-sensitive or automotive applications. The adjustable output range accommodates various logic levels, while the DFN10 package suits space-constrained designs. Ensure adequate PCB copper area for thermal dissipation given the 1.5 A capability and junction-to-ambient thermal resistance characteristics.

Part Context

The LD59150 belongs to STMicroelectronics' portfolio of ultra-low-dropout linear regulators designed for robust performance in demanding environments. It complements other LDO series by offering a unique dual-supply configuration and high current density in a small footprint. The Industrial variant serves as a cost-effective solution for non-automotive industrial and telecom applications requiring reliable power management.

Replacement Considerations

The LD59150PURY is the direct automotive-grade equivalent with identical electrical specifications but different qualification standards. No other cross-model replacements are documented in the provided datasheet.

FAQ

How is the output voltage adjusted on the LD59150PUR?

The output voltage is set between 0.8 V and 3.6 V using an external resistor divider connected to the feedback (FB) pin. The reference voltage is typically 0.8 V.

What is the function of the VBIAS pin?

The VBIAS pin provides an auxiliary bias supply ranging from 2.7 V to 5.5 V. This dual-supply design helps reduce the dropout voltage and improves efficiency compared to single-supply regulators.

How does the Power Good (PG) pin operate?

The PG pin is an open-drain output that indicates when the regulated output voltage is within the correct range. It requires an external pull-up resistor and goes low if the device is disabled or if the output voltage falls below the threshold.