STMicroelectronics LDLN025J12R

Overview

LDLN025J12R from STMicroelectronics is a 250 mA ultra-low-noise low-dropout (LDO) voltage regulator in Flip-Chip4 package, delivering 1.2 V output with ±2% accuracy across line, load, and temperature. It operates from 1.5 V to 5.5 V input, achieves 120 mV typical dropout at 250 mA, and features 6.5 µV_RMS output noise (10 Hz–100 kHz) and 80 dB PSRR at 100 Hz-optimized for powering noise-sensitive RF and analog circuits.

For engineers reviewing the LDLN025J12R datasheet, LDLN025J12R pinout, LDLN025J12R application, or LDLN025J12R equivalent, this LDO is selected for battery-powered imaging sensors, VCO biasing, precision ADC reference supplies, and mobile RF modules where ultra-low quiescent current (12 µA no-load), controlled dropout I_Q, and output discharge are critical design requirements.

Technical Context

The LDLN025J12R employs a bandgap-referenced error amplifier driving a PMOS pass transistor, enabling stable regulation with ceramic output capacitors as low as 0.7 µF. Its internal soft-start limits inrush current, while thermal shutdown (160 °C) and foldback overcurrent protection ensure robust operation under fault conditions.

Logic-controlled enable (VEN high = on, VEN low = shutdown < 1 µA) and integrated output discharge resistor (230 Ω) support clean power sequencing in multi-rail systems. The device maintains ultra-low I_Q not only at no-load but also during dropout-extending runtime in deep-sleep battery applications.

Key Specifications

Pinout & Package

LDLN025J12R uses the Flip-Chip4 package (0.628 mm × 0.628 mm, 0.410 mm height), requiring solder paste stencil and reflow profile optimized for 0.21 mm pitch micro-BGA mounting. Exposed pad must be connected to GND for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-noise LDO applications.

Compared with XC6210B122MR-G and ADP160AUJZ-1.2-R7, LDLN025J12R delivers 250 mA output, lowest noise (6.5 µV_RMS), smallest Flip-Chip4 footprint, and integrated discharge-making it optimal for next-gen compact, battery-sensitive RF and imaging systems.

Availability

LDLN025J12R is available at Aetrix Electronics and suitable for smartphone image sensors, VCO power supplies, portable instrumentation ADC references, and wireless LAN RF front-ends requiring stable component supply with guaranteed long-term manufacturability.

Supply support for LDLN025J12R 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.

LDLN025J12R belongs to ST's ultra-low-noise LDO product line, engineered specifically for powering noise-critical analog and RF circuitry in battery-constrained portable electronics.

FAQ

What is the minimum input voltage required for stable 1.2 V output at full 250 mA load?

The LDLN025J12R requires VIN ≥ VOUT + VDROP. With 120 mV typical dropout at 250 mA, minimum input is 1.32 V. However, datasheet specifies 1.5 V as absolute minimum operating input voltage to guarantee performance across temperature and process variation-so 1.5 V is the design floor.

Can LDLN025J12R be used with a 0.47 µF output capacitor?

No. The datasheet mandates COUT ≥ 0.7 µF for stability across all operating conditions. Using 0.47 µF risks oscillation or poor transient response, especially at high frequencies or light loads. Validated range is 0.7–10 µF ceramic with 5–500 mΩ ESR.

Is the exposed pad on the Flip-Chip4 package electrically connected?

Yes-the exposed pad is internally connected to GND and must be soldered to a PCB GND plane. It serves dual functions: thermal dissipation (reducing R_thJA to 210 °C/W) and low-inductance grounding for noise suppression and enable signal integrity.

Does LDLN025J12R support reverse-voltage protection on the VOUT pin?

No. The device lacks reverse-battery or reverse-current protection. If VOUT exceeds VIN (e.g., during hot-swap or backup supply scenarios), current can flow backward through the pass transistor, potentially damaging the IC. External protection diode or ideal diode controller is required in such architectures.