Monolithic Power Systems Inc. MP6508AGQ-P

Overview

MP6508AGQ-P from Monolithic Power Systems is a bipolar stepper motor driver IC integrating two N-channel full-bridge MOSFETs in a thermally enhanced QFN-16 (3mm×3mm) package. It operates from 2.7V to 18V input, delivers up to 1.2A per channel, features 250mΩ HS/LS R_DS(ON), internal charge pump, and fault reporting via open-drain FAULT pin - used in precision motion control for POS printers and security cameras.

For engineers reviewing the MP6508AGQ-P datasheet, MP6508AGQ-P pinout, MP6508AGQ-P application, or MP6508AGQ-P equivalent, key selection criteria include its dual full-bridge topology, external/internal PWM current control modes, thermal shutdown at 165°C, sleep current of 1µA, and compatibility with 2-phase stepper motors requiring microstepping-capable gate logic sequencing.

Technical Context

The MP6508AGQ-P implements two independent H-bridge drivers with integrated N-channel power MOSFETs, each supporting bidirectional current flow up to 1.2A. Its internal charge pump enables high-side gate drive without external bootstrap components, while constant off-time (t_OFF = 21–31µs) PWM current regulation uses external sense resistors and a 204mV V_REF threshold.

Control logic accepts four independent gate inputs (AIN1/AIN2/BIN1/BIN2) for full-step, half-step, or microstepping configurations. Protection circuitry includes independent over-current detection on both HS and LS FETs (IOCP1 = 2.2–4.6A, IOCP2 = 1.8–3A), UVLO (2.5V rising), and thermal shutdown with 15°C hysteresis.

Key Specifications

Pinout & Package

MP6508AGQ-P uses a QFN-16 (3mm×3mm) package with exposed thermal pad soldered to GND for optimal heat dissipation. Pin numbering follows standard JEDEC MO-220 VEED-4 layout with Pin 1 marked by corner chamfer or dot.

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, MP6508AGQ-P uniquely balances compact QFN-16 packaging, 1µA sleep current, and integrated fault signaling - making it optimal for battery-powered, space-limited motion systems where diagnostic visibility and energy efficiency are critical.

Availability

MP6508AGQ-P is available at Aetrix Electronics and suitable for point-of-sale printers, video security cameras, digital still cameras, and battery-powered educational robots requiring stable component supply across production lifecycles.

Supply support for MP6508AGQ-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 centers in the US, China, and Taiwan.

The MP6508A belongs to MPS's stepper motor driver product line, engineered for compact, thermally efficient motion control in consumer and industrial edge devices where integration, low power, and robust protection are mandatory.

FAQ

What is the maximum motor voltage supported by MP6508AGQ-P?

The MP6508AGQ-P supports input voltages from 2.7V to 18V on the VIN pin. Absolute maximum rating is 20V, but continuous operation above 18V risks exceeding safe junction temperature or violating SOA limits - operation must remain within the 2.7–18V recommended range per datasheet Section 6.

Can MP6508AGQ-P drive unipolar stepper motors?

No. MP6508AGQ-P is designed exclusively for bipolar stepper motors with center-tapped windings. Its dual full-bridge topology requires four-wire (A+, A−, B+, B−) connection and cannot interface with five- or six-wire unipolar configurations that rely on single-ended switching.

How does the internal charge pump function without external components?

The internal charge pump generates boosted gate drive voltage for high-side N-MOSFETs using an on-chip oscillator and flying capacitor. Only one external 10nF–100nF ceramic capacitor between BST and VIN is required - no diodes or large electrolytics needed - enabling fully integrated high-side drive.

What is the purpose of the blanking time (t_BLANK) in current sensing?

t_BLANK (2–3µs) disables the current-sense comparator during MOSFET switching transitions to suppress false OCP triggers caused by body diode reverse-recovery spikes or layout-induced noise - ensuring accurate current regulation without premature shutdown.

Is the FAULT pin actively driven or open-drain?

The FAULT pin is an open-drain output. It pulls low during over-current or thermal shutdown events and floats otherwise. An external pull-up resistor (typically 4.7kΩ to VDD or 3.3V) is required to generate a valid logic-high signal for MCU interrupt detection.

Does MP6508AGQ-P support microstepping?

MP6508AGQ-P supports full-step and half-step modes natively via AIN/BIN logic sequencing. Microstepping (e.g., 1/4, 1/8) requires external controller generation of intermediate current levels - the IC itself provides only the full-bridge power stage and current regulation, not native microstep waveform synthesis.

What thermal vias configuration is recommended for the exposed pad?

MPS recommends ≥4 thermal vias (0.3mm diameter, 0.5mm pitch) connecting the exposed pad directly to an internal or bottom-layer solid GND plane. Vias must be tented on outer layers and filled or plated to ensure low-impedance thermal transfer - critical to maintain θ_JA ≤50°C/W.