Monolithic Power Systems Inc. MP6540HGU-A-P

Overview

MP6540HGU-A-P from Monolithic Power Systems is a three-phase brushless DC motor power stage integrating six N-channel MOSFETs, pre-drivers, charge-pump gate drive, and bidirectional current-sense amplifiers. It delivers 5A continuous / 6A peak output across 5.5V–50V input, supports 100% duty cycle via internal charge pump, and features OCP, UVLO, and thermal shutdown. Used in compact BLDC motor control for drones and power tools.

For engineers reviewing the MP6540HGU-A-P datasheet, MP6540HGU-A-P pinout, MP6540HGU-A-P application, or MP6540HGU-A-P equivalent, key selection criteria include its QFN-26 (5mm×5mm) package, PWM/EN vs. HS/LS input variants, integrated current sensing with ±3A range, and synchronous rectification for inductive load recirculation.

Technical Context

The MP6540HGU-A-P implements three independent half-bridge drivers with matched high-side (25–29 mΩ typ.) and low-side (20–23.5 mΩ typ.) MOSFETs at 25°C, enabling precise phase-A/B/C switching. Its internal charge pump generates VCP = VIN + 5.5V at 196 kHz to sustain high-side gate drive under 100% duty cycle conditions.

Current sensing uses integrated amplifiers with 1/9200 A/A ratio (typ.), delivering proportional output current (114 µA at ±1A) referenced to VREF. Fault management includes open-drain nFAULT signaling for OCP (10–17A threshold), UVLO (4–5.5V rising), and thermal shutdown (150°C with 25°C hysteresis).

Key Specifications

Pinout & Package

MP6540HGU-A-P is housed in a thermally enhanced QFN-26 (5mm × 5mm) package with exposed thermal pad, optimized for high-current motor drive applications requiring low θJC (18.4°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP6540HGU-A-P, MP6540HGU-Z offers identical performance in tape-and-reel format for production lines, while MP6536GQ-Z trades integrated sensing and 50V capability for reduced footprint and cost in less demanding applications.

Availability

MP6540HGU-A-P is available at Aetrix Electronics and suitable for electric power tools, drone propulsion systems, and medical infusion pumps requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for MP6540HGU-A-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 converters, motor drivers, and LED controllers.

The MP6540H series belongs to MPS's integrated motor driver product line, designed specifically for space-constrained, thermally demanding BLDC applications where integration of gate drive, protection, and current sensing reduces system BOM count and improves reliability.

FAQ

What is the function of the nSLEEP pin, and how does it affect power consumption?

The nSLEEP pin places MP6540HGU-A-P into ultra-low-power sleep mode when driven logic low, reducing quiescent current to 0.75–3.5 µA. All internal circuits-including gate drivers and current sensors-are disabled. Wake-up delay is approximately 1 ms, and the pin has an internal 1 MΩ pull-down resistor for default disable.

Can MP6540HGU-A-P drive a motor directly without external gate resistors?

Yes - MP6540HGU-A-P integrates pre-drivers and gate drive power supplies, eliminating the need for external gate resistors in most applications. However, small RC snubbers (e.g., 10 Ω + 100 pF) on PWMA/B/C may be added to suppress ringing in high-dV/dt layouts, especially with long motor leads.

How is current sensing calibrated, and what reference voltage is required?

Current sensing uses a fixed 1/9200 A/A ratio. To convert SOx output current to voltage, connect an external termination resistor (R_TERM) between SOx and VREF (typically 3.3V or 5V). The resulting voltage is V_SOUT = V_REF + (I_LOAD × R_TERM) / 9200 - no calibration trim is needed for ±5% accuracy across temperature.

Does MP6540HGU-A-P support 100% duty cycle, and how is it achieved?

Yes - MP6540HGU-A-P supports true 100% high-side duty cycle using an internal charge pump that generates VCP = VIN + 5.5V. This sustains sufficient gate-source voltage for high-side MOSFETs even when PWM is continuously high, enabling zero-voltage vector operation required in advanced FOC algorithms.

What thermal design guidelines apply to the QFN-26 package?

Optimal thermal performance requires soldering the exposed thermal pad to ≥2 cm² of inner/outer copper plane with ≥6 thermal vias (0.3 mm diameter, filled or capped). Use 2 oz copper layers and minimize trace length for LSS, SA/SB/SC, and VIN paths. With this layout, θJA drops to ≤22.4°C/W, enabling 5A continuous operation at T_A ≤ 85°C.

Is there a difference between MP6540HGU-A-P and MP6540HGU-A?

No functional difference - "MP6540HGU-A-P" is the full orderable part number per MPS documentation; the "-P" suffix denotes tray packaging (vs. "-Z" for tape-and-reel). Both share identical silicon, marking (MPS prefix + year/week code + "A" suffix), QFN-26 package, and electrical specifications.

How does the automatic synchronous rectification feature improve efficiency?

When both high- and low-side FETs are off during inductive flyback, MP6540HGU-A-P automatically turns on the appropriate low-side FET (if Sx < 0V) or high-side FET (if Sx > VIN) to conduct recirculating current. This replaces lossy body-diode conduction, reducing power dissipation by up to 1.2 W per phase at 5A - critical for thermal management in sealed enclosures.