Monolithic Power Systems Inc. MP5515GU-P

Overview

MP5515GU-P from Monolithic Power Systems is a wide-input (2.7–18V), 5A bidirectional power backup manager IC with integrated hot-swap FET, I²C interface, 10-bit ADC, and capacitor health test functionality. It implements a patented single-inductor boost-buck topology for energy storage and release in enterprise SSDs and NVDIMMs, delivering up to 32V programmable storage voltage and 5A buck-load capability.

For engineers reviewing the MP5515GU-P datasheet, MP5515GU-P pinout, MP5515GU-P application, or MP5515GU-P equivalent, this device supports precise input current limiting (6A max), VB slew-rate control via DVDT pin, real-time monitoring of VIN/VB/VSTRG/temperature, and programmable OVP/RCP - all critical for fail-safe data retention in power-loss scenarios.

Technical Context

The MP5515GU-P integrates a bidirectional, single-inductor boost-buck converter with patented energy management logic that enables lossless charge transfer from VIN to STRG (boost mode) and controlled discharge from STRG to VB (buck-release mode). Its internal 14mΩ input MOSFET handles hot-swap inrush control, while reverse-current blocking prevents backup energy leakage during VIN failure.

It features a dedicated 10-bit ADC with inputs for VIN, VB, VSTRG, temperature (via thermistor on TEMP), and current sensing (ILIM monitor voltage), all accessible via I²C. The I²C interface (up to 3.4MHz) supports dynamic configuration of current limits, slew rates, cap health tests, and interrupt thresholds - enabling closed-loop system-level power supervision without external controllers.

Key Specifications

Pinout & Package

MP5515GU-P is housed in a thermally enhanced 30-pin QFN package (5mm × 5mm, 0.5mm pitch) with exposed thermal pad (PGND-connected) for efficient heat dissipation in high-current backup applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power backup management applications.

Compared with TPS650236 and LTC4041, MP5515GU-P uniquely combines bidirectional energy transfer, integrated hot-swap, full-system telemetry, and capacitor health diagnostics in a single 5mm×5mm package - making it optimal for space-constrained, high-reliability SSD/NVDIMM designs requiring deterministic power-loss response.

Availability

MP5515GU-P is available at Aetrix Electronics and suitable for enterprise SSDs, NVDIMMs, and industrial hard-disk drives requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP5515GU-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 over two decades of leadership in DC/DC conversion and power management solutions.

The MP5515GU-P belongs to MPS's Energy Backup and Management Unit product line, designed specifically to replace bulky discrete backup circuits in mission-critical storage systems - emphasizing minimal external components, deterministic failover timing, and intelligent capacitor supervision.

FAQ

What is the maximum storage capacitor voltage supported by MP5515GU-P?

The MP5515GU-P supports programmable storage voltage up to 32V via the FBS feedback network. This allows direct compatibility with common 25V and 35V tantalum or aluminum electrolytic capacitors used in SSD/NVDIMM backup circuits. The internal VSTRG absolute maximum rating is 36V, providing 4V margin for transient spikes.

How does the capacitor health test function work?

The health test uses the RTEST pin to discharge the STRG capacitor through an external resistor while measuring voltage decay via the ADC. By comparing discharge time constants against baseline values, the system infers ESR increase and capacitance loss - enabling predictive maintenance before backup failure occurs.

Can MP5515GU-P operate without an I²C host controller?

Yes - all core functions (input current limiting, UVLO/OVP protection, buck-release, and power-good signaling) operate autonomously using resistor-programmed thresholds and internal defaults. I²C is optional for advanced features like dynamic current limit adjustment, cap health testing, and telemetry readout.

What thermal performance can be expected in a 5A buck-release scenario?

With the QFN-30 package mounted on a 2-layer 63mm×63mm PCB per EV5515-U-00A reference design, θJA is 35°C/W. At 5A load and 7.5V VB, typical power dissipation is ~1.8W, resulting in ~63°C junction rise above ambient - well within the 125°C max operating temperature and thermal shutdown margin.

Is the DVDT pin required for proper VB startup?

No - DVDT is optional. When left floating, VB slew rate is controlled via I²C register bits. Connecting a capacitor (≥1nF) to AGND provides hardware-programmable soft-start, useful in systems where I²C initialization may lag behind power-on timing.

Does MP5515GU-P support simultaneous boost and buck operation?

No - it operates in mutually exclusive modes: boost (VIN → STRG) during normal input operation, and buck (STRG → VB) during input failure. The control logic ensures strict separation to prevent shoot-through and guarantee energy directionality.

What is the minimum recommended STRG capacitor value for 5A/20ms hold-up?

Based on typical efficiency and voltage droop calculations, a 1000µF/35V aluminum electrolytic capacitor is validated for 5A/20ms hold-up at 7.5V VB. Larger values (e.g., 2200µF) extend hold-up time linearly and reduce voltage sag - verified in Figure 11 of the datasheet.