Monolithic Power Systems Inc. MP6541AGQKT-P

Overview

MP6541AGQKT-P from Monolithic Power Systems is a three-phase BLDC motor power stage IC integrating six N-channel MOSFETs (15 mΩ HS/LS), three half-bridge drivers, gate pre-drivers, dual gate supply generators, and three bidirectional current-sense amplifiers. It delivers 8A continuous output current at 40V max input, supports 100% duty cycle via internal charge pump, and targets compact fan, drone, and power tool motor control systems.

For engineers reviewing the MP6541AGQKT-P datasheet, MP6541AGQKT-P pinout, MP6541AGQKT-P application, or MP6541AGQKT-P equivalent, key selection criteria include its 4.75–40V operating range, integrated OCP/UVLO/OVP/thermal shutdown, TQFN-26 (6mm×6mm) thermal performance, and HS/LS input logic architecture distinguishing it from PWM/EN variants.

Technical Context

The MP6541A implements independent high-side (HSA/HSB/HSC) and low-side (LSA/LSB/LSC) digital inputs per phase, enabling precise synchronous rectification and dead-time control without external logic. Its internal charge pump (2 MHz switching) sustains gate drive for HS-FETs across full duty cycle, while trickle-charge circuitry maintains VCP stability under transient load.

Current sensing uses matched on-die amplifiers with phase-specific gain ratios (e.g., 1/11600 typ for Phase A), delivering ±25 µA offset and rail-to-rail 0–5V output swing into ≥1.8 kΩ pull-up loads. Fault handling integrates deglitched OCP (0.4 µs), 2 ms auto-retry, and open-drain nFAULT signaling for UVLO, OVP, OTP, and over-current events.

Key Specifications

Pinout & Package

TQFN-26 (6mm × 6mm) package with exposed thermal pad (pin 18 GND) for enhanced heat dissipation; JEDEC MO-220 compliant, MSL Level 1, lead-free/halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP6541GQKT-P, the MP6541AGQKT-P offers superior control granularity for field-oriented control, while STSPIN32F0A trades discrete signal chain precision for embedded compute capability-making MP6541AGQKT-P optimal for high-fidelity current-loop implementations in thermally constrained spaces.

Availability

MP6541AGQKT-P is available at Aetrix Electronics and suitable for computer cooling fan control, drone propulsion systems, power tool motor drivers, and industrial pump controllers requiring stable component supply and long-term production continuity.

Supply support for MP6541AGQKT-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 design focus on efficiency, integration, and thermal robustness.

The MP6541A belongs to MPS's motor driver power stage product line, engineered specifically for compact, high-current BLDC/PMSM applications where board space, thermal headroom, and current measurement fidelity are critical constraints.

FAQ

What is the maximum allowable continuous current for MP6541AGQKT-P under standard PCB conditions?

The MP6541AGQKT-P delivers 8A continuous output current per phase when mounted on a 4-layer PCB with adequate copper pour and thermal vias. This rating assumes 25°C ambient, 21.4°C/W θJA, and proper external capacitor placement per datasheet layout guidelines. Peak current reaches 12A for ≤1 second under transient conditions.

How does the MP6541AGQKT-P implement 100% duty cycle operation without external charge pump components?

It uses an internal 2 MHz charge pump with integrated switches and regulation, paired with a trickle-charge circuit that maintains VCP above threshold during sustained high-side conduction. The external 1 µF capacitor between VCP and VIN provides local energy storage, eliminating need for boost converters or external diodes.

Can the current-sense outputs (SOA/SOB/SOC) be directly interfaced with a 3.3V microcontroller ADC?

Yes - each SOx pin sources/sinks current proportional to phase current (e.g., I_LOAD/11600). With a 3.3V reference and 36.3 kΩ termination resistor, full-scale 8A maps to ~2.3V, staying within 0–3.3V ADC range. Offset error (<±25 µA) introduces <0.9% gain error at full scale, acceptable for most motor control loops.

What happens during an over-current event, and how does recovery work?

When OCP triggers (e.g., HS current >19A for >0.4 µs), all six MOSFETs disable, nFAULT pulls low, and synchronous rectification decays residual current. After 2 ms, the device automatically re-enables outputs. If fault persists, the cycle repeats - no manual reset required, supporting robust operation in dynamic motor environments.

Is the nSLEEP pin compatible with standard 3.3V or 5V logic levels?

Yes - nSLEEP accepts logic-high input from 2.0V to 5.5V (VIH min = 2V) and logic-low down to 0.8V (VIL max). Its internal 500 kΩ pull-down ensures safe default sleep state if left floating, making it compatible with both 3.3V and 5V microcontrollers without level-shifting.

Does MP6541AGQKT-P support reverse current flow for regenerative braking?

Yes - the integrated current-sense amplifiers measure bidirectional current in each phase, and automatic synchronous rectification actively controls HS/LS FETs during flyback to route recirculating current through low-R_DS(on) channels instead of body diodes, enabling efficient regeneration without external circuitry.

What thermal vias configuration is recommended for the TQFN-26 exposed pad?

Use ≥9 thermal vias (0.3 mm diameter, 0.5 mm pitch) directly under the exposed pad, connecting to inner and bottom ground planes. Each via should have annular ring ≥0.15 mm; fill vias with solder or conductive epoxy to maximize thermal transfer. This achieves ~12.8°C/W θJC as specified in datasheet.