Monolithic Power Systems Inc. MP6520GV-P

Overview

MP6520GV-P from Monolithic Power Systems is a bipolar stepper motor driver IC with integrated dual full-bridge N-channel MOSFETs, microstepping translator, and 3.3V LDO regulator. It operates from 8V to 32V input, delivers up to ±1.5A per phase, supports full/half/quarter/eighth-step modes, and includes OCP/OVP/UVLO/thermal shutdown. Used in precision motion control for printers and automated lab equipment.

For engineers reviewing the MP6520GV-P datasheet, MP6520GV-P pinout, MP6520GV-P application, or MP6520GV-P equivalent, key selection criteria include its integrated gate drive charge pump, adjustable mixed-decay ratio via MDS pin, fixed 3.3V logic supply output (3P3VOUT), ROSC-based constant off-time programming, and open-drain nFAULT/nHOME status reporting.

Technical Context

The MP6520GV-P implements a constant off-time PWM current control architecture with programmable blanking time (2µs) and crossover dead time (400ns), enabling precise bipolar winding current regulation using external sense resistors and VREF scaling. Its internal charge pump (525kHz) generates high-side gate drive voltage, eliminating need for external bootstrap circuitry.

Microstep resolution is selected via MS1/MS2 logic inputs, generating 4/8/16/32 steps per electrical cycle with defined current amplitude sequences (e.g., ±70.7% in full-step, ±100% in eighth-step). Fault handling includes auto-retry OCP (5.5A trip, 1µs deglitch), latch-free thermal shutdown (165°C), and non-latching OVP (37.9V threshold).

Key Specifications

Pinout & Package

MP6520GV-P is housed in a thermally enhanced QFN-28 (4mm × 5mm) package with exposed GND pad on underside for PCB heat sinking. Pin numbering follows JEDEC MO-220 VGHD-3 standard, with Pin 1 marked by corner chamfer or dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar stepper motor driver applications.

Compared with TB6600HG and DRV8825, MP6520GV-P uniquely integrates charge pump, 3.3V LDO, nHOME indexing, and OVP-making it optimal for compact, self-contained 24V+ stepper systems needing fault resilience and absolute position recovery.

Availability

MP6520GV-P is available at Aetrix Electronics and suitable for printer paper feed control, lab automation XYZ stages, CNC router bit positioning, and medical infusion pump drives requiring stable component supply across production lifecycles.

Supply support for MP6520GV-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-efficiency analog and power ICs, with design centers in the US, China, and Taiwan.

The MP6520 product line targets compact, high-voltage stepper motor control in space-constrained industrial and medical equipment, emphasizing integration of power stages, protection, and microstepping logic in a single QFN package.

FAQ

What is the maximum allowable motor supply voltage for MP6520GV-P?

The absolute maximum VIN rating is 40V, but the recommended operating range is 8V to 32V. Operation above 32V risks triggering the input over-voltage protection (OVP) threshold of 37.9V, which disables outputs and asserts nFAULT. Sustained use near 40V may accelerate package degradation due to increased power dissipation in the 300mΩ MOSFETs.

How does the MP6520GV-P achieve microstepping without an external clock?

It uses an internal translator that advances the step sequence on each rising edge of the STEP pin, with direction set by DIR and resolution selected by MS1/MS2. No external clock is needed-the STEP signal itself serves as the timing reference, allowing flexible acceleration profiles generated directly by the host MCU.

Can the 3P3VOUT pin power a microcontroller's VCC rail?

3P3VOUT delivers 3.3V at up to 1mA with ±3.5% regulation. It can power low-current logic interfaces (e.g., GPIO, SPI level shifters) but is not rated for MCU core voltage supply, which typically requires >50mA. For full MCU power, use an external 3.3V LDO; reserve 3P3VOUT for auxiliary logic biasing only.

What thermal management is required for continuous 1.5A operation?

At 1.5A and 24V, power dissipation reaches ~1.4W in the QFN-28 package. A 4-layer PCB with ≥2 in² of 2oz copper connected to the exposed thermal pad is required to maintain junction temperature ≤125°C. Thermal resistance θJA is 40°C/W; without proper pad soldering and copper pour, die temperature will exceed safe limits within seconds.

Is the nHOME output synchronized to electrical or mechanical rotor position?

nHOME asserts low at electrical step #5 (45°), corresponding to the first full-step position in the internal lookup table-not physical rotor alignment. Mechanical homing requires coupling nHOME with an external optical or Hall-effect sensor, as the IC has no rotor position feedback; nHOME only indicates translator state index.

How does the adjustable mixed-decay mode affect motor torque and noise?

Setting MDS to 1.5V yields ~60% fast decay, improving high-speed torque by reducing current lag but increasing audible switching noise. At MDS = 0V (slow decay), torque drops above 300 RPM but acoustic noise falls below 15kHz. The optimal MDS voltage balances torque retention against EMI and acoustic requirements for each mechanical load.

Does the OCP circuit monitor current during both high-side and low-side conduction?

Yes-the over-current protection senses current through both high-side and low-side MOSFETs independently using dedicated comparators not shared with the PWM current control path. This allows OCP to trigger even during slow-decay freewheeling or fast-decay recirculation, protecting against shoot-through, winding shorts, and ground faults.