VNH7040AYTR

STMicroelectronics VNH7040AYTR: Automotive 38 V, 35 A Fully Integrated H-Bridge Motor Driver

Overview

The STMicroelectronics VNH7040AYTR is a fully integrated H-bridge motor driver designed for high-current brushed DC motor control in automotive body and comfort applications. Built on ST’s VNH family platform, it integrates the high-side and low-side MOSFETs, current sensing, diagnostics, and protection features into a compact, thermally enhanced PowerSSO-36 package with an exposed pad. With a maximum operating voltage of 38 V, up to 35 A output capability, and a typical combined RDS(on) of 40 mΩ (HS+LS), the VNH7040AYTR balances efficiency, simplicity, and robustness for space-constrained automotive designs.

The part number suffix “TR” denotes tape-and-reel packaging, making the VNH7040AYTR production-ready for automated assembly lines. Its control interface supports PWM, INx, and EN/DIAG signals, which enables straightforward implementation of speed control, direction control, and fault feedback in typical ECU architectures.

Key Benefits and Use Cases

• Fully integrated H-bridge simplifies the bill of materials compared to discrete MOSFET H-bridges and shunt-based sensing.
• 38 V capability targets automotive supply environments where load transients and cold-crank conditions must be considered at the system level.
• 35 A output supports demanding actuators found in window lifters, seat adjusters, and sunroof mechanisms.
• Typical total RDS(on) of 40 mΩ (HS+LS) improves conduction efficiency and reduces thermal dissipation for a given load current.
• Current sensing, diagnostic reporting, and protection features help designers meet functional safety and reliability goals at the system level.
• PowerSSO-36 with exposed pad supports efficient heat extraction via PCB copper and thermal vias, fitting modern high-density ECUs.

Where the VNH7040AYTR Fits

The device is purpose-built for automotive brushed DC motors, especially body electronics and comfort systems that require reliable torque delivery and straightforward control. Common targets include window lifters, mirror and door-lock actuators, seat motors, and sunroof drives. Outside of automotive, it is also a strong candidate for robust general-purpose brushed DC motor control where supply voltages and currents are within the stated limits.

Detailed Specifications

• Brand / Manufacturer: STMicroelectronics
• Series: VNH
• Category: Motor Driver ICs
• MPN: VNH7040AYTR
• Motor Driver Type: Full H-Bridge
• Max Operating Voltage: 38 V
• Output Current (max): 35 A
• RDS(on) (HS+LS): 40 mΩ (typical, total)
• Control Interface: PWM, INx, EN/DIAG
• Package: PowerSSO-36 (Exposed Pad)
• Pin Count: 36
• Mounting Type: Surface Mount
• Packaging: Tape & Reel (TR)

Not specified in datasheet (from the provided data): minimum/nominal supply voltage, current sense gain, PWM frequency range, undervoltage thresholds, detailed protection trip points, and thermal resistance numbers. Refer to the official STMicroelectronics datasheet for complete electrical characteristics and timing parameters.

Functional Overview

• H-Bridge topology: The VNH7040AYTR integrates both high-side and low-side power MOSFETs, allowing forward, reverse, brake, and coast modes for brushed DC motors.
• Command and control: PWM input(s) support speed regulation, while INx lines control the H-bridge state and motor direction. The EN/DIAG pin is typically used to enable the output stage and to report diagnostic conditions to the host MCU.
• Built-in sensing and diagnostics: The device includes current sensing and diagnostic reporting. Designers can use these signals for load monitoring, stall detection, or system-level fault handling.
• Protection features: The part integrates protection mechanisms (see datasheet for details). These are key for automotive reliability and for safeguarding the device, motor, and wiring harness under abnormal conditions.

Package, PCB, and Thermal Notes

• Package: PowerSSO-36 with an exposed thermal pad
• Mechanical: 36 pins in a compact, thermally enhanced surface-mount form factor compatible with automated pick-and-place
• Thermal strategy: The exposed pad is intended to be soldered to a substantial copper area on the PCB, ideally with a network of thermal vias to inner or bottom copper planes. This improves heat spreading away from the silicon and enhances reliability at high load currents.
• Layout guidance (general best practices):
• Keep the high-current loop between the supply, the H-bridge, and the motor as short and wide as possible.
• Use low-inductance routes and provide adequate bulk and high-frequency decoupling near the device supply pins.
• Separate sensitive sense and logic traces from high dV/dt switching nodes.
• Consider star-grounding to minimize shared impedance coupling.

Applications

• Automotive brushed DC motor control
• Automotive body motors
• Window lifter modules
• Seat and sunroof control
• Mirror and door lock actuators
• General-purpose brushed DC motor drivers where robustness and integration are priorities

System Integration and Control Interface

• PWM control: Use PWM to set motor speed; duty cycle maps to average motor voltage. Select a PWM frequency compatible with your EMC plan and system requirements. Not specified in datasheet: preferred PWM frequency range.
• Direction control: INx lines determine H-bridge conduction quadrant, enabling forward/reverse, brake, and coast modes.
• Enable/diagnostic: EN/DIAG is typically used both to enable the driver and to report diagnostic status to the host MCU. Fault logic details are application-dependent; refer to the datasheet for pin behavior and timing.
• Current sensing: Integrated sensing can be used for closed-loop torque control, stall detection, and overload protection. Calibration and scaling depend on system-level design and datasheet parameters (not provided here).

Reliability and Protection Considerations

The VNH7040AYTR includes protection and diagnostic functions that are essential in automotive environments. While the provided data does not enumerate specific trip levels or timing, these integrated features are intended to:

• Help prevent damage under fault conditions such as motor stalls or short circuits.
• Provide diagnostic visibility to a host MCU via EN/DIAG or dedicated sense outputs.
• Reduce the need for numerous external sensing and protection components.

Given the automotive focus, system designers should also consider:

• External supply transient protection appropriate to the vehicle’s electrical environment.
• Proper derating with respect to ambient temperature, copper area, and airflow.
• EMC/EMI mitigation in layout and harness design.

Consult the datasheet for definitive protection behaviors and limits.

Sourcing, Lifecycle, and Supply Chain

• Lifecycle status: Active (source: STMicroelectronics product page)
• Replacements: None listed in the provided data
• Approved alternates: None listed in the provided data
• Inventory: 0 units on hand in this listing at the time of writing
• Orderable P/N: VNH7040AYTR (TR indicates tape-and-reel packaging)

Practical sourcing notes:

• Tape-and-reel is suited for high-volume SMT production; confirm reel diameter and orientation against your feeder setup.
• If your AVL requires multiple sources, consider evaluating other STMicroelectronics VNH family members with compatible electrical ranges or footprints. Specific drop-in alternates are not specified in datasheet; verify pinout and thermal characteristics before substitution.
• For long-term programs, align your qualification and PPAP requirements with the manufacturer’s documentation and plan for potential life-cycle notifications.

Compliance and Environmental

• RoHS status: RoHS Compliant
• Other environmental and regulatory marks (e.g., REACH, ELV, halogen-free): Not specified in datasheet
• Automotive qualification (e.g., AEC-Q100): Not specified in datasheet

Always reference the official STMicroelectronics documentation for the latest declarations and compliance certificates.

Design-In Checklist

• Electrical limits:
• Verify your nominal and maximum supply voltage remain within the 38 V maximum specification (include transient considerations at the system level).
• Validate load current against the 35 A maximum and derate based on thermal performance of your PCB and enclosure.
• Control strategy:
• Define PWM duty-cycle limits and motor startup profiles to manage inrush and thermal rise.
• Implement diagnostic monitoring via EN/DIAG and current sense for fault handling and in-field reliability.
• PCB and thermal:
• Reserve adequate copper area under the exposed pad with thermal vias to inner planes.
• Route high-current paths with wide traces and short lengths; minimize loop areas.
• Compliance and testing:
• Plan EMC testing around your chosen PWM frequency and edge rates.
• Validate thermal behavior under worst-case ambient and load conditions.

Frequently Asked Questions (FAQs)

Q: What is the maximum operating voltage of the STMicroelectronics VNH7040AYTR?
A: 38 V.

Q: How much output current can the VNH7040AYTR deliver?
A: Up to 35 A, according to the provided specifications.

Q: What is the total RDS(on) of the integrated MOSFETs?
A: 40 mΩ typical (HS+LS combined), per the provided data.

Q: What control signals does it support?
A: PWM, INx, and EN/DIAG control interface signals.

Q: What package does the STMicroelectronics VNH7040AYTR use?
A: PowerSSO-36 with an exposed thermal pad, suitable for surface-mount assembly.

Q: Is this device automotive qualified?
A: Not specified in datasheet (based on the provided information). Consult STMicroelectronics documentation for formal qualification status.

Q: Does it include current sensing and diagnostics?
A: Yes. The device integrates current sensing and diagnostic features.

Q: Is this a full H-bridge driver for brushed DC motors?
A: Yes. It integrates both high-side and low-side MOSFETs for forward, reverse, brake, and coast operation.

Q: Are there recommended PWM frequency ranges?
A: Not specified in datasheet in the provided data. Refer to the official datasheet for guidance and limits.

Q: Are there listed replacements or approved alternates?
A: None are listed in the provided data.

Resources

• Datasheet: https://www.st.com/resource/en/datasheet/vnh7040ay.pdf
• Product page: https://www.st.com/en/automotive-analog-and-power/vnh7040ay.html

Note: All parameters and features listed here are based on the provided part data and the referenced STMicroelectronics resources. If a parameter is not included above, consider it “Not specified in datasheet” in this context and verify details in the official documentation before final design decisions.