Monolithic Power Systems Inc. MP6515GL-Z

Overview

MP6515GL-Z from Monolithic Power Systems is a 35V, 2.8A peak-current H-bridge motor driver IC in a 20-pin QFN (3mm × 4mm) package with exposed thermal pad. It integrates four N-channel MOSFETs, supports PHASE/ENABLE logic control, provides internal current sensing via VISEN, and delivers ±1.5A continuous output current for DC brush motors and solenoids in industrial motion control systems.

For engineers reviewing the MP6515GL-Z datasheet, MP6515GL-Z pinout, MP6515GL-Z application, or MP6515GL-Z equivalent, key selection considerations include its 5.4–35V input range, cycle-by-cycle current regulation without external shunt, 0.25Ω HS/LS R_DS(on), fault reporting via open-drain nFAULT, and compatibility with 3.3V/5V logic interfaces.

Technical Context

The MP6515GL-Z implements constant off-time PWM current regulation using internal sensing of low-side MOSFET conduction, with trip threshold set by ISET resistor (100 µA/A scaling) and VISEN output calibrated to 1.5V at current limit. Its gate drive uses an integrated charge pump (680 kHz) to sustain high-side N-MOS operation across the full input range.

Control logic decodes PHASE, ENBL, BRAKE, and BMODE inputs to configure forward/reverse/brake (low/high/sync fast decay) states, while nSLEEP disables all circuitry including the charge pump. Fault detection is independent of current regulation-over-current (3.2–5A), over-voltage (36–40V), UVLO (5.3V rising), and thermal shutdown (165°C) each assert open-drain nFAULT.

Key Specifications

Pinout & Package

MP6515GL-Z is housed in a thermally enhanced 20-pin QFN package (3mm × 4mm, 0.5mm pitch) with exposed thermal pad requiring solder connection to PCB ground plane for optimal thermal performance (θ_JA = 48°C/W, θ_JC = 10°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar H-bridge motor driver applications.

Compared with TB6612FNG and VNH7040AS, MP6515GL-Z offers balanced integration-retaining simple logic control while delivering 35V operation, shuntless current sensing, and thermal performance in a compact QFN, making it optimal for industrial and medical motion control where reliability and ease of implementation are critical.

Availability

MP6515GL-Z is available at Aetrix Electronics and suitable for industrial valve actuation, medical infusion pumps, robotics joint control, and automotive HVAC blower systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP6515GL-Z 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 analog and power ICs, with core expertise in DC/DC conversion, motor control, and LED drivers.

The MP6515 belongs to MPS's H-bridge motor driver product line, engineered for robust, integrated control of brushed DC motors and solenoids in space-constrained, thermally demanding environments such as industrial automation and portable medical equipment.

FAQ

What is the function of the ISET pin, and how is current limit set?

The ISET pin sources a precision 100µA/A reference current. Connecting a resistor (R_ISET) from ISET to GND sets the VISEN scaling factor (V_VISEN = 100µA × R_ISET × I_LOAD). When VISEN reaches 1.5V, cycle-by-cycle current regulation activates - so R_ISET = 10kΩ yields a 1.5A trip point. This eliminates external shunts while enabling programmable, temperature-stable current limiting.

Does MP6515GL-Z require external capacitors for the charge pump, and what values are specified?

Yes - MP6515GL-Z requires two external ceramic capacitors: a 100nF flying capacitor between CPA and CPB pins, and a 100nF reservoir capacitor between VCP and VIN. These are mandatory for high-side gate drive functionality; omission causes failure to turn on upper MOSFETs above ~8V input, resulting in asymmetric output drive and potential motor stall.

How does the nFAULT pin behave during current regulation versus over-current fault?

nFAULT is asserted low only during hard faults - over-current protection (OCP), over-temperature (OTP), or over-voltage (OVP). It remains high during normal cycle-by-cycle current regulation, even at repeated trip events. This distinction allows systems to distinguish between intentional current limiting (e.g., torque control) and dangerous fault conditions requiring shutdown.

Can MP6515GL-Z drive a bipolar stepper motor, and what limitations apply?

Yes - MP6515GL-Z can drive one winding of a bipolar stepper motor using external logic to sequence PHASE/ENBL/BRAKE. However, it controls only one H-bridge channel; driving a full 2-phase stepper requires two MP6515GL-Z units or a dedicated dual-channel driver. Its 2.8A peak rating suits NEMA 11–14 frame steppers, but microstepping requires external PWM modulation of PHASE/ENBL timing.

What thermal design guidance applies to the QFN-20 package's exposed pad?

The exposed thermal pad (EP) must be soldered to a solid copper GND plane with ≥4 thermal vias (0.3mm diameter, spaced ≤1mm apart) connecting to inner/ground layers. The recommended land pattern matches JEDEC MO-220; insufficient pad area or via count raises θ_JA beyond 48°C/W, risking thermal shutdown at >1.2A continuous load in still-air conditions.

Is MP6515GL-Z compatible with 3.3V microcontrollers, and how are logic thresholds defined?

Yes - MP6515GL-Z accepts 3.3V logic levels directly. Input logic 'low' is defined as ≤0.8V (V_IL), and 'high' as ≥2.0V (V_IH), with input leakage <±20µA. Its internal 515kΩ pull-down resistors ensure defined states on PHASE, ENBL, BRAKE, and BMODE during MCU reset or floating conditions, preventing unintended motor activation.