onsemi LV8728MR-AH Stepper Motor Driver (Dual H-Bridge, SOIC-30W)
The onsemi LV8728MR-AH is a compact stepper motor driver designed for engineers who need a robust, surface-mount solution for bipolar stepper control up to approximately 32 V. Part of the LV8728 family, this device integrates two full H-bridges (four half-bridges) in a 30-pin wide-body SOIC package, streamlining motor drive design in printers, scanners, robotics, and general motion systems. Typical family-level capabilities include PWM current regulation and essential protection features such as thermal shutdown, overcurrent protection, and undervoltage lockout—always verify exact ratings and behavior in the official datasheet.
If you are sourcing a reliable, widely supported dual H-bridge stepper motor driver, the onsemi LV8728MR-AH offers a balanced mix of integration, package convenience, and power capability for a wide range of embedded motion applications.
At-a-Glance Features and Benefits
- Brand and series: onsemi LV8728 family
- MPN: LV8728MR-AH
- Topology: Dual H-Bridge (Quad Half-Bridge)
- Motor type: Bipolar stepper
- Outputs: 4 (two H-bridges)
- Max supply voltage: 32 V
- Package: SOIC-30W (wide-body), 30 pins
- Mounting: Surface Mount
- Typical family features (verify in datasheet):
- PWM current regulation for smooth torque control
- Protection features such as thermal shutdown, overcurrent, and undervoltage lockout
Benefits for your design:
- Reduces external component count by integrating both H-bridges in a single IC
- Simplifies PCB layout versus discrete MOSFET H-bridge approaches
- Compact SOIC-30W package eases assembly and supports high-volume production
- Suitable for a broad range of stepper applications from office automation to robotics
Where the LV8728MR-AH Fits
The LV8728MR-AH is well-suited for motion applications that need dependable, repeatable positioning and moderate power handling in a surface-mount form factor. Typical end applications include:
- Printers and office automation
- Scanners
- Robotics and motion control
- General-purpose stepper motor drives
Its dual H-bridge topology targets bipolar stepper motors, enabling bidirectional control and fine current regulation (family-level capability) that can reduce resonance and improve low-speed smoothness. The 32 V maximum supply supports extended torque and speed ranges relative to low-voltage drivers, making this part a flexible choice when your system operates above typical 12 V rails.
Specifications
The following list summarizes key information available for the onsemi LV8728MR-AH. If a parameter is not included in the provided data, it is noted as not specified.
- Manufacturer: onsemi
- Series: LV8728
- Category: Stepper Motor Drivers
- MPN: LV8728MR-AH
- Topology: Dual H-Bridge (Quad Half-Bridge)
- Motor type: Bipolar stepper
- Outputs: 4
- Max supply voltage: 32 V
- Package: SOIC-30W
- Pin count: 30
- Mounting type: Surface Mount
- Packaging: Not specified in datasheet
- Operating temperature range: Not specified in datasheet
- Output current capability: Not specified in datasheet
- Logic interface/levels: Not specified in datasheet
- Microstepping support: Not specified in datasheet
- PWM/chopper frequency details: Not specified in datasheet
- Protection features: Family-level indication of thermal shutdown, overcurrent, undervoltage lockout (verify exact device behavior in the datasheet)
- Certifications/Environmental compliance: Not specified in datasheet
Notes:
- Some specifications vary by configuration and operating conditions. Verify absolute maximum ratings, output current capability, pinout, and control timing in the official datasheet.
Package and Pinout Considerations
- Form factor: SOIC-30W (wide-body) supports surface-mount assembly and offers comfortable pin pitch for routing power and sense lines.
- Pin functions: Refer to the LV8728MR-AH datasheet for detailed pin descriptions, recommended connections, and any required external components (e.g., current-sense resistors, bootstrap capacitors, or charge pump components if applicable).
- Thermal: Thermal performance depends on PCB copper area, vias, and ambient conditions. Follow the datasheet’s thermal and layout guidance for power planes and heat spreading.
Design and Integration Guidance
While exact control-mode options and current ratings must be confirmed in the datasheet, the following best practices apply broadly to dual H-bridge stepper drivers and will help you realize the full potential of the onsemi LV8728MR-AH in your design.
Power and Decoupling
- Place bulk capacitance near the motor supply input to handle current transients when phases switch.
- Add high-frequency ceramic decoupling near supply pins. Distribute multiple capacitors across different values to cover a wide frequency range.
- Ensure adequate voltage headroom relative to the 32 V maximum and include margin for surge and back-EMF events.
Current Regulation and Sense Layout
- If the driver uses external sense resistors (typical in PWM current regulation), use low-inductance, precision shunts and short, symmetric return paths.
- Keep sense traces away from noisy switching nodes. Use Kelvin connections where recommended.
- Tuning the current regulation scheme (e.g., blanking time, decay mode, or similar parameters if available) should be based on the datasheet and lab validation to minimize audible noise and torque ripple.
Grounding and EMI
- Use a solid ground reference with a star or split-ground strategy to isolate high di/dt motor currents from logic/reference grounds.
- Route high-current paths with short, wide traces, and avoid long loops that can radiate.
- If needed, add snubbers or RC dampers per datasheet recommendations to mitigate ringing.
Thermal Management
- Estimate conduction and switching losses under worst-case motor current and duty cycles.
- Increase copper area under and around power pins to improve heat dissipation.
- Validate with thermal imaging or on-board sensors during worst-case ambient and load conditions.
Control Interface
- The specific control interface (e.g., step/dir, phase/enable, or serial configuration) must be verified in the LV8728 datasheet.
- Debounce and filter control signals where appropriate and respect timing requirements provided by the manufacturer.
Applications and Use Cases
Printers and Office Automation
Stepper mechanisms in paper handling, carriage positioning, and scanning modules benefit from the integrated dual H-bridge architecture. The LV8728MR-AH supports clean current regulation (family-level capability) for quieter operation and improved low-speed smoothness, which can be important in office environments.
Scanners
Precise motion over a fixed scan path requires stable current control and predictable phase switching. The LV8728MR-AH’s integration reduces board area, enabling compact scan-head assemblies and lower overall system cost.
Robotics and Motion Control
From small robotic arms to XY platforms, stepper motors offer reliable open-loop control. With a supply up to 32 V, the LV8728MR-AH can help achieve higher step rates and better torque at speed than lower-voltage drivers, subject to system thermal constraints and the motor’s own characteristics.
General-Purpose Stepper Motor Drives
Lab equipment, vending mechanisms, point-of-sale devices, and instrument panels frequently standardize on bipolar steppers. The LV8728MR-AH’s SOIC-30W package and surface-mount construction make it practical for high-mix or high-volume builds.
Lifecycle, Supply Chain, and Replacements
- Lifecycle status: Not specified; consult onsemi’s product page for the latest status.
- OCM source: onsemi
- Drop-in replacements: None specified in the provided data.
- Second sources and alternates: Not provided. If second sourcing is required, consider drivers with similar topology (dual H-bridge for bipolar steppers), voltage range, and package footprint—but verify pin compatibility, thermal capacity, control logic, and protection behaviors.
Sourcing tips:
- Validate lead times and inventory with authorized distributors listed by onsemi.
- Confirm the exact part number suffixes (e.g., tape-and-reel, RoHS codes) before placing orders.
- If migrating from another LV8728 variant, compare pinouts and any configuration differences line-by-line in the datasheet.
Compliance and Environmental
- RoHS status: Not specified in datasheet
- REACH/Green compliance: Not specified in datasheet
- Halogen-free status: Not specified in datasheet
- MSL (Moisture Sensitivity Level): Not specified in datasheet
For formal quality documentation and environmental declarations, request compliance certificates directly from onsemi or consult the product page’s compliance section.
Practical Selection Checklist
Use this quick checklist when shortlisting the onsemi LV8728MR-AH for your design:
- Electrical fit
- Bipolar stepper motor, two phases required
- System bus voltage compatible with up to 32 V maximum
- Output current capability meets motor requirements (verify in datasheet)
- Control scheme
- Interface and logic levels supported by your MCU/FPGA
- Microstepping/resolution needs met (verify in datasheet)
- Thermal
- PCB area, copper weight, and airflow sufficient for worst-case load
- Protections
- Required safeguards (OCP, TSD, UVLO) present and configured appropriately
- Compliance
- RoHS/REACH and corporate environmental requirements satisfied
- Mechanical
- SOIC-30W footprint available; assembly process supports the package
Frequently Asked Questions (FAQs)
Q: What is the onsemi LV8728MR-AH?
A: It is a stepper motor driver that integrates two H-bridges (four half-bridges) to drive a bipolar stepper motor in a surface-mount SOIC-30W package.
Q: What is the maximum supply voltage?
A: Up to approximately 32 V as provided in the part data. Always check the datasheet for absolute maximum ratings and recommended operating ranges.
Q: Which motor types are supported?
A: Bipolar stepper motors.
Q: How many outputs does the LV8728MR-AH have?
A: Four outputs, arranged as two full H-bridges.
Q: Does the LV8728MR-AH support PWM current regulation?
A: PWM current regulation is a typical feature of the LV8728 family; verify exact configuration and parameters in the LV8728MR-AH datasheet.
Q: What protection features are available?
A: Family-level information indicates thermal shutdown, overcurrent protection, and undervoltage lockout; consult the datasheet for definitive device behavior and thresholds.
Q: What is the package and pin count?
A: SOIC-30W with 30 pins.
Q: Is microstepping supported?
A: Not specified in the provided data. Refer to the datasheet to confirm microstepping capability and resolution, if available.
Q: What is the output current rating?
A: Not specified in the provided data. See the datasheet for maximum and recommended drive current and any derating guidance.
Q: Can this driver control two brushed DC motors instead of a stepper?
A: The device integrates two H-bridges, which can in some contexts drive two brushed DC motors; however, the LV8728MR-AH is intended for bipolar stepper control. Confirm permissible operating modes and limitations in the official documentation.
Resources
- Product page: https://www.onsemi.com/products/motor-drivers/stepper-motor-drivers/lv8728
- Datasheet: https://www.onsemi.com/pdf/datasheet/lv8728-d.pdf
Final Notes
The onsemi LV8728MR-AH combines a dual H-bridge topology, 32 V supply capability, and a practical SOIC-30W package to simplify bipolar stepper control in compact systems. Many details—such as current ratings, exact control interface, microstepping support, and timing—must be confirmed in the datasheet. For sourcing, verify lifecycle status and compliance directly on the onsemi product page, and align the device’s electrical, thermal, and mechanical characteristics with your system requirements before committing to production.