LD49300PT12R

Overview

The LD49300PT12R is a fixed-output, 3 A very low-dropout linear voltage regulator manufactured by STMicroelectronics. It operates with an input voltage range of 1.4 V to 5.5 V and requires a bias supply between 3 V and 6 V. The device provides a fixed output voltage of 1.2 V with ±1.5% initial tolerance at 25 °C. Maximum dropout voltage is 400 mV at 3 A load over the operating temperature range. Junction temperature ranges from -25 °C to +125 °C.

Feature Summary

• Dual-supply architecture utilizing separate main input (VIN) and bias input (VBIAS) ports to minimize dropout voltage.
• Logic-controlled shutdown capability via an active-high enable pin for power management.
• Integrated thermal shutdown and current limit protection mechanisms.
• Stable operation with small ceramic capacitors, requiring a minimum output capacitance.

Applications

• Graphics processors
• PC add-in cards
• Microprocessor core voltage supply
• Low voltage digital ICs

Procurement Notes

Verify component authenticity through authorized distribution channels. Confirm package integrity upon receipt, as the PPAK housing relies on PCB copper planes for thermal dissipation. Ensure design compliance with absolute maximum ratings, particularly regarding VIN and VBIAS limits. Review datasheet specifications for electrical characteristics under intended operating conditions before integration.

Selection Notes

Select this regulator when high bandwidth and fast transient response are required for low-power microprocessors. The dual-supply configuration allows ultra-low input voltages on the main rail while maintaining regulation. Verify that the application can provide the necessary bias voltage headroom above the output level. Consider thermal resistance calculations based on PCB copper area if ambient temperatures approach maximum junction limits.

Part Context

The LD49300PT12R belongs to the LD49300 family of high-bandwidth, low-dropout regulators designed for high-current applications. This specific part number denotes the fixed 1.2 V output version packaged in PPAK format. The series supports adjustable outputs starting from 0.8 V and fixed options ranging up to 1.8 V, catering to various core voltage requirements.

Replacement Considerations

Public confirmed substitute part numbers: None identified.