Monolithic Power Systems Inc. MP5505EGL-P

Overview

MP5505EGL-P from Monolithic Power Systems is a lossless energy storage and management unit designed for solid-state and hard-disk drive power-backup systems. It integrates input current limiting (4.5A max), bidirectional buck/boost energy transfer, programmable bus voltage slew rate, power-on reset, and reverse-current protection in a QFN-20 (3mm×4mm) package. It delivers up to 4A sustained release current with 30mΩ internal disconnect switch and supports 2.7V–7V input.

For engineers reviewing the MP5505EGL-P datasheet, MP5505EGL-P pinout, MP5505EGL-P application, or MP5505EGL-P equivalent, key selection criteria include programmable storage voltage (VIN to 30V), adjustable release voltage (2.7V–6V), thermal shutdown at 150°C, and dual open-drain power-good indicators (PGIN/PGS) with 20μs response.

Technical Context

The MP5505EGL-P implements a patented bidirectional buck/boost architecture: during normal operation, its boost converter charges an external storage capacitor to a user-set voltage (e.g., 12V) using a 500kHz fixed-frequency COT control loop; during input outage, it switches to buck mode to discharge stored energy into the VB bus at regulated release voltage (e.g., 4.2V). The internal 70mΩ high-side and 60mΩ low-side power switches enable efficient energy transfer with minimal external components.

Start-up sequencing is controlled via DVDT (programmable dV/dt slew rate) and TPOR (adjustable power-on reset delay), while ILIM sets input current limit (3.1–4.1A with 1.4kΩ resistor) and EN/ENCH provide independent enable control for system-level power management. Reverse-current protection prevents backfeed from STRG to VIN during release.

Key Specifications

Pinout & Package

MP5505EGL-P is housed in a thermally enhanced QFN-20 (3mm×4mm) package with exposed thermal pad. Pin functions are validated per MPS MP5505E Rev. 1.01 datasheet and confirmed on official Monolithic Power Systems documentation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar energy storage and management applications.

Compared with MAX34451ETL+ and TPS650231RSLR, MP5505EGL-P uniquely integrates programmable inrush control, bidirectional energy transfer, and dual power-good signaling in one QFN-20 package-reducing total solution size by >40% and eliminating external MOSFETs and controllers required by alternatives.

Availability

MP5505EGL-P is available at Aetrix Electronics and suitable for solid-state drives, hard-disk drives, and industrial data loggers requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant sourcing.

Supply support for MP5505EGL-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 power management ICs, with over two decades of innovation in DC/DC conversion, motor drivers, and energy management solutions.

The MP5505E product line was developed specifically for compact, high-efficiency energy hold-up in storage subsystems-addressing the growing demand for reliable, capacitor-based backup in SSDs, HDDs, and edge computing modules.

FAQ

What is the maximum storage voltage supported by MP5505EGL-P?

The MP5505EGL-P supports storage voltages up to 30V, as confirmed by absolute maximum rating VSTRG = –0.3V to 35V and recommended operating condition VSTRG = VIN to 30V. This enables efficient 5V-to-12V or 5V-to-20V energy pumping, significantly reducing required storage capacitance versus lower-voltage alternatives.

How does MP5505EGL-P prevent accidental release during startup?

MP5505EGL-P uses separate EN and ENCH pins with strict sequencing requirements: ENCH must remain low until VB reaches regulation (confirmed by PGIN high), avoiding premature activation of the buck-release path. The TPOR pin adds a programmable delay (0.4ms default) before VB charging begins, further isolating release logic from startup transients.

Can MP5505EGL-P operate without external diodes?

No-MP5505EGL-P requires an external Schottky diode (e.g., DFLS240) between SW and PGND during buck release mode to conduct low-side current and prevent shoot-through. The datasheet explicitly states this diode is mandatory for safe operation under high-current release conditions.

What is the role of the CST pin, and how is it used?

CST is the high-side switch driving voltage storage node. It holds charge for the internal high-side gate driver during buck release mode. A 100nF ceramic capacitor must be placed between CST and STRG to ensure stable bootstrap operation-critical for maintaining 100% duty cycle capability when depleting stored energy down to VB UVLO.

How is input current limit accuracy affected by temperature?

Input current limit (ILIM) varies from 3.1A to 4.1A across –40°C to +125°C at RILIM = 1.4kΩ, per electrical characteristics table. This ±0.5A variation reflects inherent MOSFET R_DS(on) drift and is fully characterized-not a production tolerance spread-ensuring predictable inrush behavior across industrial temperature ranges.

Is MP5505EGL-P compatible with lead-free reflow profiles?

Yes-MP5505EGL-P is qualified for standard lead-free reflow per J-STD-020, with peak temperature rating of 260°C and moisture sensitivity level (MSL) 3. Its QFN-20 (3mm×4mm) package uses NiPdAu lead finish and meets IPC/JEDEC standards for automated assembly reliability.