Monolithic Power Systems Inc. MP8903DJ-2.5-LF-P

Overview

MP8903DJ-2.5-LF-P from Monolithic Power Systems is a 150mA low-dropout linear regulator in TSOT23-5 package, operating from 2.7V to 6.5V input and delivering fixed 2.5V output with ±2% accuracy. It features 100mV dropout at 100mA, thermal shutdown protection, and stable operation with low-ESR ceramic capacitors. Used for powering mobile handset PLL circuits and audio codec bias rails where compact size and precision regulation are critical.

For engineers reviewing the MP8903DJ-2.5-LF-P datasheet, MP8903DJ-2.5-LF-P pinout, MP8903DJ-2.5-LF-P application, or MP8903DJ-2.5-LF-P equivalent, key selection criteria include dropout voltage at 150mA load, FB threshold voltage (1.222V), EN logic thresholds (1.5V high / 0.4V low), thermal shutdown trigger (155°C), and compatibility with 1μF–10μF X5R/X7R output capacitors.

Technical Context

The MP8903DJ-2.5-LF-P employs a PMOS pass transistor architecture enabling low dropout performance across its full 150mA load range. Its internal bandgap reference (1.222V) feeds a precision error amplifier that regulates output via feedback from the FB pin, supporting both fixed-output and adjustable configurations.

Thermal protection operates with 155°C trip point and 30°C hysteresis, ensuring safe shutdown under sustained overload or high ambient conditions. The EN pin provides active-high enable control with sub-1μA shutdown current, allowing precise power sequencing in multi-rail systems.

Key Specifications

Pinout & Package

MP8903DJ-2.5-LF-P uses the TSOT23-5 surface-mount package (2.9mm × 1.6mm × 1.0mm), optimized for space-constrained portable electronics. Exposed pad is not present; thermal dissipation relies on copper area connected to GND pin.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6206P252MR and AP2210K-2.5TRG1, MP8903DJ-2.5-LF-P delivers superior dropout performance (100mV vs ≥250mV), tighter output accuracy (±2% vs ±3%), and robust EN logic (1.5V/0.4V thresholds), making it optimal for space- and power-constrained RF and audio subsystems.

Availability

MP8903DJ-2.5-LF-P is available at Aetrix Electronics and suitable for mobile handset PLL power, audio codec bias supply, and 802.11 PC card core logic requiring stable component supply, RoHS-compliant packaging, and guaranteed long-term availability.

Supply support for MP8903DJ-2.5-LF-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with design centers in the US, China, and Taiwan, and global manufacturing partnerships.

The MP8903 belongs to MPS's precision low-noise LDO product line, engineered specifically for noise-sensitive RF, audio, and portable applications where small footprint, low dropout, and thermal resilience are mandatory.

FAQ

Can MP8903DJ-2.5-LF-P be used in adjustable-output configuration?

No - MP8903DJ-2.5-LF-P is factory-configured for fixed 2.5V output and lacks internal resistor network flexibility. Only MP8903 variants with "DX" or "DG" suffixes (e.g., MP8903DX-X.X) support adjustable operation via FB pin. This part's FB pin is internally tied and must remain unconnected in standard use.

What is the maximum allowable power dissipation for MP8903DJ-2.5-LF-P at 60°C ambient?

Using θJA = 220°C/W for TSOT23-5, maximum continuous power dissipation at TA = 60°C is calculated as (125°C − 60°C) / 220°C/W = 295mW. Exceeding this causes thermal shutdown; actual safe limit depends on PCB copper area and airflow.

Is an input capacitor mandatory, and what value is recommended?

Yes - a ceramic capacitor of 1μF to 10μF (X5R or X7R dielectric) is mandatory between IN and GND. Values ≥2.2μF improve line transient response; placement within 2mm of the IN pin is critical to prevent oscillation and ensure stability.

Does MP8903DJ-2.5-LF-P require a feed-forward capacitor for stability?

No - feed-forward capacitance across R1 is optional and only improves transient response in adjustable configurations. For fixed 2.5V operation, stability is guaranteed with standard 1μF–10μF output capacitance and no additional components.

What is the minimum load current required for regulation?

No minimum load is required - MP8903DJ-2.5-LF-P maintains regulation from 0mA to 150mA. Quiescent current is 100μA typical, enabling reliable operation even under ultra-light loads such as RTC backup or sensor biasing.

How does thermal shutdown behave during repeated fault events?

Upon reaching 155°C junction temperature, the device shuts down output and remains off until junction cools by ≥30°C (to ≤125°C), then auto-restarts. This hysteresis prevents thermal cycling and latch-up during sustained overload or poor heatsinking.

Can EN pin be left floating in system design?

No - EN must be actively driven. Floating EN risks indeterminate state due to leakage currents; tie to IN via 100kΩ resistor for automatic startup or to GND via 100kΩ for default-off behavior. Direct connection to IN is recommended for simplicity.