Monolithic Power Systems Inc. MPQ8903DJ-2.5-LF-Z

Overview

MPQ8903DJ-2.5-LF-Z from Monolithic Power Systems is an industrial-grade 150mA low-dropout linear regulator with fixed 2.5V output, 2% accuracy, 100mV dropout at 100mA, 2.7V–6.5V input range, and thermal shutdown protection. It operates across –40°C to +85°C and is used in mobile handset PLL power rails where stable low-noise biasing is required.

For engineers reviewing the MPQ8903DJ-2.5-LF-Z datasheet, MPQ8903DJ-2.5-LF-Z pinout, MPQ8903DJ-2.5-LF-Z application, or MPQ8903DJ-2.5-LF-Z equivalent, key selection criteria include dropout voltage under load, FB reference voltage tolerance, EN logic thresholds, thermal shutdown hysteresis, and TSOT23-5 package thermal resistance (θJA = 220°C/W).

Technical Context

The MPQ8903DJ-2.5-LF-Z uses a PMOS pass transistor architecture enabling low dropout operation and compatibility with low-ESR ceramic output capacitors (1µF–10µF, X5R/X7R). Its internal 1.222V bandgap reference feeds a precision feedback loop that maintains ±2% output accuracy over temperature and line/load variations.

Enable control is implemented via a dedicated EN pin with 1.5V high-threshold and 0.4V low-threshold, supporting automatic startup when tied to IN. Thermal protection activates at 155°C with 30°C hysteresis, ensuring safe recovery without external circuitry.

Key Specifications

Pinout & Package

MPQ8903DJ-2.5-LF-Z is housed in a 5-pin TSOT23 package (2.9mm × 1.6mm × 0.9mm), optimized for thermal dissipation (θJA = 220°C/W) and space-constrained industrial PCBs. The exposed pad variant is not specified; standard TSOT23-5 thermal performance applies.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2502E/MB and TPS7A2025PDQNR, MPQ8903DJ-2.5-LF-Z uniquely combines industrial temperature qualification, integrated EN control, thermal hysteresis, and 100mV dropout at 100mA - making it optimal for thermally constrained, sequenced, and battery-sensitive RF/analog subsystems.

Availability

MPQ8903DJ-2.5-LF-Z is available at Aetrix Electronics and suitable for mobile handset PLL power, audio codec bias rails, 802.11 PC card regulation, and industrial sensor signal conditioning requiring stable component supply across extended temperature ranges.

Supply support for MPQ8903DJ-2.5-LF-Z 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 MPQ8903 belongs to MPS's industrial-grade linear regulator product line, engineered specifically for reliable operation in harsh thermal and electrical environments where precision, low noise, and long-term stability are mandatory.

FAQ

What is the maximum continuous output current of the MPQ8903DJ-2.5-LF-Z?

The MPQ8903DJ-2.5-LF-Z delivers up to 150mA continuously under recommended operating conditions (T_A ≤ +85°C, θ_JA = 220°C/W, C_OUT ≥ 1µF). At 100mA, dropout is 100mV; at 150mA, dropout rises to 150mV for V_OUT = 2.5V. Derating is required above +85°C ambient per thermal resistance limits.

Can the MPQ8903DJ-2.5-LF-Z be configured for adjustable output voltage?

Yes - although shipped with a factory-trimmed 2.5V fixed output, the device supports adjustable operation from 1.25V to 5V by connecting an external resistor divider between OUT and FB. The FB pin references 1.222V, and R1+R2 must not exceed 100kΩ to avoid loading errors. Standard 1% resistors are recommended for accuracy.

What is the purpose of the EN pin, and what logic levels activate it?

The EN pin provides active-high enable control: driving it ≥1.5V turns the regulator on, while ≤0.4V disables output and reduces quiescent current to 0.1–2µA. For automatic startup, EN may be directly connected to IN. No pull-up or pull-down is required, and the pin draws only 0.01–2µA bias current across temperature.

Does the MPQ8903DJ-2.5-LF-Z require specific capacitor types for stability?

Yes - stability is guaranteed with 1µF–10µF X5R or X7R ceramic capacitors on both IN and OUT pins. These dielectrics maintain capacitance over temperature and DC bias. Other types (e.g., Y5V, Z5U, or electrolytics) are not recommended due to significant capacitance loss and potential instability.

How does thermal protection behave during overload conditions?

When junction temperature reaches 155°C, the MPQ8903DJ-2.5-LF-Z shuts down output and enters thermal limiting. It remains off until temperature falls by 30°C (to ~125°C), then automatically resumes regulation. This hysteresis prevents cycling and ensures safe recovery without external intervention or reset signals.

What is the significance of the FB reference voltage tolerance?

The FB pin regulates to 1.222V with ±0.027V (±2.2%) tolerance over –40°C to +85°C. When used in adjustable mode, this directly impacts output accuracy: for example, a 2.5V output set by R1/R2 inherits this reference error, contributing to overall ±2% total output tolerance when combined with resistor and load effects.

Is the TSOT23-5 package RoHS-compliant and lead-free?

Yes - the "-LF" suffix in MPQ8903DJ-2.5-LF-Z explicitly denotes RoHS-compliant, lead-free packaging per JEDEC J-STD-020. The TSOT23-5 footprint conforms to JEDEC MO-193 variation AA, and reflow profiles follow standard Pb-free guidelines with peak temperature ≤260°C.