Monolithic Power Systems Inc. MP6500LGU-P

Overview

MP6500LGU-P from Monolithic Power Systems is a bipolar stepper motor driver IC with integrated current sensing, translator logic, and dual full-bridge power stages. It operates from 4.5V to 35V, delivers up to 2.5A per phase (PCB/thermal dependent), supports full/half/quarter/eighth-step microstepping, and integrates over-current, over-voltage, UVLO, and thermal shutdown protections. It is used in precision motion control systems such as industrial printers and automated lab equipment.

For engineers reviewing the MP6500LGU-P datasheet, MP6500LGU-P pinout, MP6500LGU-P application, or MP6500LGU-P equivalent, this page provides verified technical context, validated pin functions, confirmed microstepping behavior, real-world thermal derating guidance, and direct alternative comparisons for stepper motor drive design.

Technical Context

The MP6500LGU-P implements a constant-off-time (COT) PWM current regulation architecture using internal MOSFETs (195mΩ HS-FET, 170mΩ LS-FET) and an on-die current-sense circuit-eliminating external sense resistors. Its translator accepts STEP/DIR/MS1/MS2 inputs to sequence two independent H-bridges driving AOUT1/AOUT2 and BOUT1/BOUT2 windings.

Protection logic operates independently of regulation: OCP triggers at ≥6A (sinking/sourcing), OVP activates at 37.5V ±1.5V, UVLO engages below 3.3V, and thermal shutdown occurs at 165°C with 15°C hysteresis. Fault status is reported via open-drain nFAULT, while ROSC sets tOFF (e.g., 200kΩ → 23µs), and ISET resistor programs peak current (e.g., 71kΩ → 1.0A).

Key Specifications

Pinout & Package

MP6500LGU-P uses a thermally optimized QFN-24 (5mm × 5mm) package with an exposed thermal pad (EP, Pin 24) for efficient heat dissipation. The package complies with JEDEC MO-220 and supports reflow soldering per IPC/JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TB6600HG and DRV8825, MP6500LGU-P offers superior integration (no sense resistors, built-in charge pump), tighter protection coverage (OVP + OTP + UVLO + OCP), and smaller footprint-making it optimal for industrial motion control where reliability, board area, and thermal performance are critical.

Availability

MP6500LGU-P is available at Aetrix Electronics and suitable for industrial printers, automated lab equipment, 3D printer motion control, and CNC engraving systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP6500LGU-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, including DC/DC converters, LED drivers, motor drivers, and battery management solutions.

The MP6500L product line is designed specifically for compact, high-efficiency bipolar stepper motor drive applications-emphasizing integration, thermal resilience, and robust protection in space-constrained industrial and automation systems.

FAQ

What is the maximum continuous motor current supported by MP6500LGU-P?

The MP6500LGU-P supports up to ±2.5A per phase under typical PCB thermal conditions (4-layer board, 2oz copper, 1in² thermal pad). Actual current capability depends on ambient temperature, airflow, and copper pour area-derating begins above 85°C junction temperature per the 36°C/W θJA specification.

How does the internal current sensing work without external resistors?

The MP6500LGU-P uses on-die MOSFET channel resistance monitoring combined with precision analog circuitry to measure current flow through each half-bridge. This eliminates external sense resistors while maintaining ±5% trip accuracy across 38–100% of full-scale current, as specified in the Electrical Characteristics table.

Can MP6500LGU-P operate with a 3.3V logic supply only?

Yes. All digital inputs (STEP, DIR, ENBL, nSLEEP, MS1, MS2) accept 3.3V logic levels directly-no level shifting required. The device's internal logic supply is derived from VIN, and input thresholds (VIL = 0.8V, VIH = 2.1V) ensure compatibility with both 3.3V and 5V microcontrollers.

What happens when nFAULT goes low, and how is it cleared?

nFAULT asserts low on OCP, OVP, thermal shutdown, or UVLO. It remains latched low until the fault condition is removed AND either nSLEEP is toggled (low→high) or VIN is power-cycled. An external pull-up resistor (typically 4.7kΩ to 3.3V/5V) is required to detect the high-impedance release state.

Is the QFN-24 package lead-free and RoHS compliant?

Yes. MP6500LGU-P is lead-free, halogen-free, and fully compliant with the EU RoHS Directive. MPS confirms green status on its official Quality Assurance page, and the device meets JEDEC MSL Level 2a moisture sensitivity requirements for standard SMT assembly.

How is microstepping resolution selected, and what are the timing constraints?

Microstepping mode is set by MS1 and MS2 logic levels (L/L = full, H/H = eighth-step). Both pins have internal pull-downs. Setup and hold times of ≥200ns relative to the STEP rising edge are required-verified in the Timing Characteristics table and Figure 1.

Does MP6500LGU-P support fast decay, slow decay, or automatic decay?

It implements automatic decay mode: starts in slow decay, then switches to fast decay if current remains above the trip threshold at the end of the fixed off-time. This adaptive behavior ensures accurate current regulation across diverse motor inductances and speeds without manual configuration.