Monolithic Power Systems Inc. MP6540HGU-P

Overview

MP6540HGU-P from Monolithic Power Systems is a three-phase brushless DC motor driver integrating six N-channel MOSFETs, pre-drivers, gate drive power supplies, and bidirectional current-sense amplifiers in a single QFN-26 (5mm×5mm) package. It delivers 5A continuous / 6A peak output current, supports 5.5V–50V input voltage, and features internal charge pump enabling 100% duty cycle operation - used in compact BLDC motor control for drones, power tools, and HVAC blowers.

For engineers reviewing the MP6540HGU-P datasheet, MP6540HGU-P pinout, MP6540HGU-P application, or MP6540HGU-P equivalent, key selection criteria include its integrated current-sense ratio (1/9200), HS+LS R_DS(on) of 45mΩ, thermal shutdown at 150°C, and nFAULT open-drain fault reporting - all critical for closed-loop motor control system validation.

Technical Context

The MP6540HGU-P implements three independent half-bridge drivers with separate enable/PWM inputs per phase (MP6540H variant), automatic synchronous rectification to reduce body-diode conduction loss, and integrated current sensing that measures only low-side FET current in both directions with ±1% gain accuracy over temperature.

Its charge pump architecture generates high-side gate drive voltage referenced to VIN, supported by external CP1–CP2 (100nF) and VCP–VIN (1µF) capacitors; the VG rail is regulated to ~5.5V via internal LDO and requires a 4.7µF bypass capacitor to ground for stable low-side gate drive.

Key Specifications

Pinout & Package

MP6540HGU-P is housed in a thermally enhanced QFN-26 (5mm × 5mm) package with exposed thermal pad, rated MSL 1, and compatible with standard reflow profiles. Pin numbering follows top-view orientation with pin 1 marked by index area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar three-phase BLDC motor driver applications.

Compared with MP6540HA-GU-Z, MP6540HGU-P offers simpler PWM-based control with fewer required MCU pins, while versus STSPIN32F0A it delivers higher current capacity, superior current-sense accuracy, and greater flexibility in motor algorithm implementation - making it optimal for industrial-grade BLDC systems demanding robustness and precision.

Availability

MP6540HGU-P is available at Aetrix Electronics and suitable for power tools, drone ESCs, HVAC blowers, and industrial pumps requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP6540HGU-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 expertise in DC-DC converters, motor drivers, and LED controllers.

The MP6540H product line targets compact, high-efficiency three-phase BLDC motor control in space- and thermal-constrained applications - emphasizing integration, protection robustness, and precision current sensing without external components.

FAQ

What is the maximum allowable PCB temperature rise for continuous 5A operation?

With the recommended 4-layer PCB layout (≥200mm² 2oz copper under exposed pad, ≥6 thermal vias), junction-to-ambient thermal resistance (θ_JA) is 22.4°C/W. At 5A continuous and 45mΩ total R_DS(on), power dissipation is ~1.125W, resulting in ~25°C rise above ambient - well within the 125°C max operating junction temperature limit.

Can MP6540HGU-P drive a motor with 100% duty cycle without external bootstrap components?

Yes. Its integrated charge pump with trickle-charge circuit maintains sufficient high-side gate voltage even at 100% duty cycle, eliminating the need for external bootstrap diodes or capacitors - unlike discrete gate driver solutions that require careful dead-time management and external charge paths.

How does the current-sense amplifier handle reverse current during regeneration?

The internal current-sense amplifiers measure low-side FET current in both forward and reverse directions with matched gain (1/9200 A/A). During regenerative braking, negative current flows through the LS-FET, producing a proportional sinking current at SOx - enabling accurate bidirectional current monitoring for FOC algorithms without polarity-switching circuitry.

Is nFAULT asserted during sleep mode?

No. When nSLEEP is driven low, all internal circuits including protection blocks are disabled, and nFAULT is released (high-impedance). Fault reporting resumes only after nSLEEP returns high and the 3–10ms start-up delay completes - ensuring no spurious fault signals during low-power states.

What external capacitors are mandatory for stable operation?

Four capacitors are mandatory: 4.7µF X7R ceramic from VG to GND; 1µF X7R from VCP to VIN; 100nF X7R between CP1 and CP2; and ≥100µF bulk input capacitor at VIN. All must be placed adjacent to respective pins with short, low-inductance traces to prevent oscillation and ensure gate drive stability.

Does MP6540HGU-P support field-oriented control (FOC)?

Yes. Its three independent current-sense outputs (SOA/SOB/SOC), precise 1/9200 ratio, and fast OCP response (0.4µs deglitch) provide the real-time, high-fidelity phase current data required for FOC implementation. Combined with external MCU-based Clarke/Park transforms, it enables smooth, high-efficiency sinusoidal commutation.

What is the minimum PWM frequency for reliable synchronous rectification?

Synchronous rectification operates reliably down to DC (0Hz) - the internal comparator continuously monitors Sx voltage relative to GND and VIN. However, for optimal efficiency at low speeds, PWM frequencies ≥10kHz are recommended to minimize switching losses while maintaining sufficient resolution for current-loop control bandwidth.