When we talk about building anything that moves from a small robot arm to an automated vehicle we’re really talking about motor control.
Motors are the muscles of any electromechanical system, converting electrical energy into motion. But just like muscles, they need a brain and nerves to work properly that’s where controllers and drivers come in.
Think of motor control as a system made of layers, like an onion.
Layered Motor Control Architecture
- Motor (Actuator): At the core is the motor—the actuator that converts electrical energy into rotational or linear motion.
- Motor Driver (Power Stage): Surrounding it is the motor driver, which takes low-power control signals and translates them into the higher voltages and currents the motor requires. Think of it as the amplifier that handles the power electronics and switching.
- Motor Controller (Control Logic): Above that sits the motor controller, which interprets commands such as “spin at 200 RPM” or “move 90° clockwise, ” and generates the necessary PWM waveforms or commutation signals the driver understands. It often implements control loops (for torque, speed, or position) and sensor processing (e.g., Hall sensors, encoders, current sensing).
- System Controller (Application Brain): At the top is the system controller—your Arduino, Raspberry Pi, or embedded CPU—coordinating motion logic, path planning, safety, and communications with the rest of the system.
Why this modular design matters
This separation improves flexibility, reliability, and scalability. The system controller isn’t burdened with fast, high-current switching. The motor driver doesn’t need to interpret high-level goals. The motor controller bridges the gap, ensuring precise, efficient motion. When each layer focuses on its role, you get cleaner designs, easier debugging, and better performance.
Electric Actuators:Motion in Many Forms
In robotics and automation, most actuators are electrical—they convert electricity into motion and typically fall into two categories:
- Rotational actuators: brushed DC motors, brushless DC (BLDC) motors, steppers, and servos. They differ in how they generate rotation, how they are commutated, and how precisely we can control their torque/position/speed.
- Linear actuators: mechanisms that turn rotation into straight-line motion (e.g., lead screws, ball screws, belt drives, and integrated linear actuators), useful for lifting, pushing, and sliding.
Across these types, the same core relationships apply:
- Speed is primarily a function of applied voltage (countered by back-EMF).
- Torque is primarily a function of current (through the motor’s torque constant).
- Control quality depends on how intelligently we regulate voltage and current, often with feedback.
Open-Loop vs. Closed-Loop Control
- Open-loop control assumes the motor responds as commanded. For example, we set a PWM duty cycle and expect proportional speed. This simplicity can be sufficient for predictable loads or where missed steps/speed variation are acceptable—like fans or lightly loaded steppers operated with margin.
- Closed-loop control measures what the motor actually does (via encoders, Hall sensors, or current/voltage feedback) and corrects errors in real time. This enables accurate torque, speed, and position regulation despite changing loads, supply variations, or friction. Examples include BLDC field-oriented control (FOC) with current and speed loops, or servo control with position and velocity loops.
- Closed-loop control adds feedback. The system measures what the motor is actually doing—using encoders, Hall sensors, resolvers, or back-EMF/current sensing—and adjusts the command to match the target speed, torque, or position. This is how BLDC systems, servos, and high-precision applications achieve accuracy and stability even under changing loads and supply conditions.
Whether open-loop or closed-loop, modern motor control generally follows the same layered structure: controller → driver → motor → feedback (optional).
Choosing the right motor and driver Your application dictates the motor type:
- Brushed DC motors are simple, low-cost, and easy to drive—great for basic motion and fast prototyping.
- BLDC motors remove mechanical brushes and use electronic commutation, delivering higher efficiency, speed capability, and longevity.
- Stepper motors move in fixed steps for excellent open-loop positioning accuracy; they are common in 3D printers, CNC machines, and camera sliders. They can also be closed-loop with encoders for higher torque utilization and reliability.
- Servos combine a motor, sensor, and controller into one integrated unit for plug-and-play precision positioning; “servo” may refer to hobby-grade PWM servos or industrial servo drives.
Matching motor to driver Each motor type pairs with its own driver and control approach—from simple half-bridge drivers for brushed DC motors to integrated three-phase solutions for BLDC and stepper applications. Choosing the right combination means matching voltage and current ratings to your supply and load, selecting a control style (open-loop, speed control, torque control, position control), and layering the system so each part does its job efficiently.
Now, let’s look deeper into each major motor family DC, BLDC, and Stepper and explore how Infineon’s dedicated driver and controller solutions bring these layers together for practical, efficient, and scalable motion control.
DC Motor Basics & Choosing the Right DriverDC motors are the most direct way to turn electrical energy into motion. Apply a voltage, and the shaft spins; reverse the polarity, and it spins in the opposite direction. What makes them so useful is how easily we can control both speed and direction but only if we match them with the right driver.
When selecting a DC motor driver, three electrical characteristics define the pairing. The first is motor voltage, which is simply the supply your motor is designed for. The driver must safely handle this voltage range, ideally with a little extra headroom. The second is average current, the amount of current the motor draws under normal load. The driver must handle that continuously without overheating. Finally, there’s stall current: the large surge that occurs if the rotor is blocked or during heavy startup. The driver must tolerate this briefly without shutting down or burning out. Once those limits are understood, controlling the motor becomes a matter of power routing. Inside every DC motor driver sits an H-bridge, four transistors arranged like the letter H, with the motor forming the crossbar.
By closing one diagonal pair, current flows one way and the motor spins forward, close the opposite pair and it reverses. Open them all and the motor stops. Some drivers can even short both sides briefly to brake the motor.
To adjust speed, we use Pulse Width Modulation. Rather than lowering voltage, PWM rapidly switches it on and off, varying how long each pulse stays high. A short pulse keeps the motor slow, a long pulse lets it spin faster. The result is smooth speed control and full torque efficiency, ideal for robotics, fans, and precise actuators.
Infineon’s modern drivers use MOSFETs instead of older bipolar transistors, which means less voltage loss(0.1V compared to 0.7V), less heat, and far better efficiency, a big deal when running from batteries.
Most Infineon drivers simplify control to just two signals: one for PWM (speed) and one for direction. Some include an enable input or diagnostic pin, but the principle stays the same.
Now that we understand how to match a driver to a motor, let’s look at how Infineon’s lineup covers different voltage and current levels.
TLE94112 – Multi Half-Bridge Driver
The TLE94112 is a multi-motor driver that integrates 12 MOSFET half-bridges, which can be configured as independent outputs, combined into full H-bridges, or paralleled for higher current. It supports SPI communication and includes built-in PWM generators for speed control, along with standard protection and diagnostic features such as overcurrent, open-load, under/over-voltage, and thermal shutdown. The device operates from 4 V to 40 V, provides about 0.9 A continuous current per half-bridge, up to 1.5 A peak, and can deliver 3.6 A when channels are paralleled. This makes it suitable for multi-motor control systems in small-scale robotics or similar applications.
Platform examples and Hackster.io projects
BTN7030 – Smart High-Current Half-Bridge
The BTN7030 is a high-current half-bridge driver from Infineon’s MOTIX™ family, designed for medium-power DC motors. It operates over a 6 V to 18 V nominal range (up to about 28 V extended) and can supply around 7 A continuous current per channel. The device supports PWM control up to 2 kHz and uses a simple PWM + direction interface for bidirectional motor control. It also includes current-sense output with roughly 5% accuracy, off-state diagnostics, and integrated protection against over-temperature, over-current, and voltage transients. This combination provides a compact and efficient solution for reliable medium-power motor control.
BTN9970LV / BTN9990LV – NovalithIC+™ Motor Control Shield
The Motor Control Shield with BTN9970LV and BTN9990LV has 60 A min overcurrent detection and can work with up to 40V. It combines two smart half-bridge drivers capable of controlling either one bidirectional DC motor or two independent motors. Both devices share the same architecture, integrating logic-level control (IN/EN), current sense and diagnostic outputs (IS1/IS2), and robust MOSFET stages for efficient operation with low losses. They include built-in protection against over-current, over-temperature, and short circuits, as well as active clamping for safe switching. The shield supports PWM speed control and connects directly to Arduino-compatible boards such as the Uno R3, making it straightforward to integrate with various microcontroller platforms using the Infineon motix-btn99x0 library.
Platform examples and Hackster.io projects
Brushless DC motor (BLDC)Unlike brushed DC motors, brushless DC (BLDC) motors won’t spin just by applying power. They require an electronic controller that coordinates the three stator windings in the correct sequence to generate a rotating magnetic field. Each winding carries a phase current 120° apart, and by energizing them in the right order, the controller makes the rotor’s permanent magnets follow the field producing rotation.
To achieve maximum torque, the stator field is kept about 90° ahead of the rotor’s magnetic field, a technique known as Field-Oriented Control (FOC). Maintaining that phase relationship demands feedback from the rotor typically from Hall sensors or a magnetic encoder so the controller knows where the rotor is at all times. This feedback is what distinguishes BLDCs from brushed motors: brushed motors can run open-loop, but BLDCs rely on sensor or sensorless feedback for smooth, efficient operation.
As with brushed DC motors, the power compatibility between motor and driver must be checked: the voltage, continuous current, and peak (stall) current must all fall within the driver’s limits. But BLDC systems go further. The controller is not just a power amplifier. it’s a complete system combining a microcontroller, gate driver, and MOSFET power stage. It handles tasks like commutation, PWM generation, current sensing, and often advanced algorithms like FOC.
When choosing a BLDC solution, your application defines the control type:
• Position control (closed-loop FOC, with encoder feedback): for robotics, gimbals, and precision systems.
• Speed control (open- or closed-loop Hall-sensor-based): for pumps, fans, and general motion.
• Torque control (current-based FOC): for systems requiring precise force feedback or smooth acceleration.
Infineon’s BLDC product line covers all these needs, from compact half-bridge ICs to full 3-phase integrated motor control shields.
IFX007T: Half-Bridge Driver for Custom FOC Systems
The IFX007T is a smart high-current half-bridge driver capable of up to 40 V and 55 A (typical). It’s an ideal building block for custom FOC (Field-Oriented Control) systems where you want full flexibility. for example, when using an Arduino-compatible MCU with the SimpleFOC library. It has no onboard MCU, so you provide the logic and feedback processing yourself. Pair it with magnetic or Hall sensors to build a closed-loop position or torque control system. Its integrated protection and low RDS(on) MOSFETs make it efficient and robust.
Platform examples and Hackster.io projects
Closed-Loop Motor Control with SimpleFOC, IFX007 and TLE5012
BLDCSHIELD_TLE9879TOBO1 – Integrated 3-Phase FOC Shield
The BLDCSHIELD_TLE9879TOBO1 combines a 3-phase gate driver, MOSFET power stage, and ARM® Cortex-M3 MCU (TLE9879) into a single compact shield. It supports sensorless and Hall-sensor-based FOC, providing smooth, quiet operation and full speed control out of the box. It’s designed to stack directly on an Arduino or other MCU board, with Infineon’s software library managing PWM generation, commutation, and protection. It runs from 6 V to 28 V and is rated for around 150 W total motor power.
BLDCSHIELD_TLE956XTOBO1 – Compact BLDC System IC Shield
The BLDCSHIELD_TLE956XTOBO1 is based on the TLE9563-3QX system IC and provides a cost-effective BLDC solution for speed and torque control. It integrates three half-bridges, a gate driver, and protection circuitry for 5.5 V to 28 V operation. With built-in support for Hall sensors, reverse-polarity protection, and SPI configuration, it’s suited for pumps, fans, small drives, and automotive auxiliaries where you need efficient 3-phase control but not precise position feedback.
Infineon BLDC Controller Comparison
Summary
• IFX007T For developers who want full control flexibility. Combine with your own MCU and FOC algorithm (e.g., SimpleFOC) for position or torque control.
• TLE9879 Shield – A ready-to-use, software-driven 3-phase FOC platform for smooth speed control or torque regulation using Hall sensors.
• TLE956X Shield – A compact, integrated BLDC solution ideal for speed control applications like fans or pumps.
Stepper Motor ControlStepper motors bridge the gap between simple DC motors and sophisticated servo systems offering accurate, gearless motion with no need for continuous feedback sensors.
A stepper motor moves in small, fixed increments, or steps. Inside, it has multiple coils arranged around a toothed rotor made of permanent magnets. By energizing these coils in a specific sequence, the magnetic field pulls the rotor from one stable position to the next. The controller sends pulses, each pulse commanding one discrete step so the motor’s movement is inherently digital and predictable.
Because every pulse equals one fixed angular movement, stepper motors can move to precise positions without needing an encoder. For example, a common 1.8° stepper motor completes 200 steps per full rotation. By changing the step frequency, we control speed, by counting pulses, we control position. This makes them perfect for 3D printers, CNC machines, and camera sliders anywhere you need precise, controlled motion at moderate speed.
Where BLDCs rely on closed-loop feedback and FOC algorithms, steppers can often run open-loop the accuracy comes from the motor design itself. However, this simplicity comes at a trade-off: steppers are not meant for high-speed applications and can lose torque if driven too fast. But for low-speed, high-precision motion, they’re unbeatable.
Infineon Stepper Motor Control Shield (IFX9201 + XMC1300)
Infineon’s Stepper Motor Control Shield is designed to make stepper motion control easy and reliable, even for beginners. Built around two IFX9201 H-bridge drivers and an XMC1300 microcontroller, it forms a complete dual-coil bipolar stepper driver system capable of controlling the two phases of a stepper motor directly.
The shield accepts a STEP and DIR input from an external controller (like an Arduino or XMC board), while the onboard XMC1300 MCU manages fast PWM generation and current control. Together, they deliver smooth, accurate stepping across a wide range of speeds.
It supports peak coil currents up to 6 A (around 2 A continuous per phase), making it suitable for most NEMA 17 and NEMA 23 class stepper motors. The driver uses PWM current regulation to safely control coil current even when the supply voltage is higher than the motor’s rated voltage, improving torque without overheating.
The shield can operate in Full Step, Half Step, or Microstep modes:
• Full Step: energizes both coils fully for each move, giving strong torque but coarser movement.
• Half Step: alternates single- and dual-coil activation, doubling resolution and improving smoothness.
• Microstep: controls coil current sinusoidally for ultra-fine positioning and near-silent operation.
A built-in potentiometer lets you adjust current limits directly on the board, protecting both motor and driver. The shield interfaces cleanly with XMC1100 Boot Kit, XMC4700 Relax Kit, or other 5 V-compatible platforms, but can also be used with generic microcontrollers via standard step/direction signals.
Inside the board, the two IFX9201 bridges handle the power stages, while the XMC1300 performs timing, current regulation, and signal conditioning, leaving your main microcontroller free to handle higher-level logic or communication tasks.
This makes the Infineon Stepper Motor Control Shield an ideal teaching and prototyping platform for projects that demand precise angular control without the complexity of closed-loop feedback.
Key Specifications:
Operating Voltage: 6 V – 24 V typical
Peak Current per Coil: up to 6 A
Continuous Current per Coil : 2 A (depends on cooling and duty)
Control Inputs: STEP, DIR, DIS (enable/disable)
🔗 Full guide and library setup on Hackster.io: Infineon Stepper Motor Control Shield Article
ConclusionFrom simple DC motors to precise steppers and efficient BLDC systems, every motion project starts with the same idea, controlled energy turned into movement. Infineon’s shields and drivers make that journey easy, whether you’re learning, prototyping, or building something big.
Explore our motor control page and Hackster projects to dive deeper, try new examples, and see how far you can take your next motion design.
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