STMicroelectronics LD49150PT10R

Overview

LD49150PT10R from STMicroelectronics is a 1.5 A ultra-low-dropout linear voltage regulator with fixed 1.0 V output, dual-supply architecture (VIN and VBIAS), ±1.5% initial output accuracy at 25 °C, 200 mV dropout at 1.5 A load, and operation down to 1.4 V main input voltage. It powers microprocessor core supplies in PC add-in cards and graphics processors where fast transient response and low-noise regulation are critical.

For engineers reviewing the LD49150PT10R datasheet, LD49150PT10R pinout, LD49150PT10R application, or LD49150PT10R equivalent, key selection factors include its dual-rail biasing scheme, 10 MHz bandwidth, thermal/current protection, ceramic-capacitor stability, and PPAK DFN6 (3×3 mm) package compatibility with high-density PCB layouts.

Technical Context

The LD49150PT10R implements a dual-input architecture: VIN (1.4–5.5 V) supplies power to the output stage, while VBIAS (3–6 V) independently powers internal control circuitry-enabling ultra-low dropout and sub-100 ns transient response. Its reference voltage is trimmed to 0.8 V ±1.2% over temperature, feeding an error amplifier that drives a low-R_DS(on) PMOS pass device.

It features active-high enable (EN) with 0.4 V shutdown / 1.4 V turn-on thresholds, integrated thermal shutdown (T_J > 150 °C), foldback current limiting (2.5 A peak), and stable operation with ≥1 µF ceramic output capacitance. The regulator requires no minimum load and supports seamless power sequencing when VBIAS settles before VIN.

Key Specifications

Pinout & Package

LD49150PT10R is housed in a thermally enhanced PPAK DFN6 (3×3 mm) package with exposed thermal pad soldered to PCB ground plane. The 6-pin layout supports high-current routing and low-inductance bypassing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-dropout linear regulator applications.

Compared with TPS7A8101DRBR and ADP1740ACPZ-1.0-R7, LD49150PT10R uniquely supports 1.4 V VIN via dedicated VBIAS, enabling operation in next-gen low-voltage systems where other 1.0 V LDOs fail to regulate - critical for legacy-compatible 1.0 V core domains fed from aging battery or energy-harvesting sources.

Availability

LD49150PT10R is available at Aetrix Electronics and suitable for graphics processor core supplies, PC add-in card power delivery, and microprocessor core voltage regulation requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LD49150PT10R includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The LD49150 belongs to ST's high-performance analog power management portfolio, engineered specifically for low-voltage, high-current core regulation in computing and graphics subsystems where traditional LDOs cannot meet both dropout and transient performance targets.

FAQ

What is the minimum required output capacitance for stable operation?

The LD49150PT10R requires a minimum 1 µF ceramic capacitor (X5R/X7R) placed directly at the VOUT pin for guaranteed stability across temperature and load. While 1 µF suffices for most applications, ST recommends 10 µF for optimal transient response - especially when VIN exceeds 4 V or fast load steps exceed 1 A/µs.

Can the EN pin be left unconnected?

No - the EN pin must never be left floating. If always-on operation is required, EN must be hard-wired to VIN. Leaving EN unconnected risks erratic startup behavior or unintended shutdown due to noise coupling, as the input threshold is defined only between 0.4 V (shutdown) and 1.4 V (enable).

How does the dual-supply architecture improve performance over single-rail LDOs?

The separate VBIAS rail powers only the error amplifier and reference, isolating control-loop stability from VIN fluctuations. This allows the pass device to operate with <200 mV headroom while maintaining 10 MHz bandwidth - impossible in single-rail LDOs where reduced VIN degrades both dropout and transient response simultaneously.

Is thermal derating required for continuous 1.5 A operation in a standard 4-layer PCB?

Yes - at 1.5 A with 1.4 V VIN and 1.0 V VOUT, power dissipation is ~0.6 W. With the PPAK package's θ_JA ≈ 60 °C/W on a 4-layer board with 250 mm² copper pour, junction temperature rise is ~36 °C. Derating is needed above 89 °C ambient to stay within the 125 °C T_J limit; thermal vias under the GND tab are strongly recommended.