STM32F446RET6

STMicroelectronics STM32F446RET6 | STM32F4 Cortex-M4F MCU with FPU, 512 KB Flash, LQFP-64

The STMicroelectronics STM32F446RET6 is a 32-bit ARM Cortex-M4F microcontroller tailored for performance-oriented embedded designs that need efficient signal processing, a robust peripheral mix, and dependable operation in industrial and consumer environments. As a member of the STM32F4 series, the STM32F446RET6 combines up to 180 MHz CPU performance with a single-precision floating-point unit (FPU), approximately 128 KB of SRAM, and 512 KB of embedded Flash. Delivered in a compact 64-pin LQFP (10×10 mm, 0.5 mm pitch) and mounted via standard surface-mount technology, it fits well into space-conscious PCBs while offering a generous I/O count and rich connectivity.

Engineers will appreciate the balance of compute and peripherals: USB 2.0 Full-Speed OTG for device or host roles, a bxCAN interface for robust networked control, 12-bit ADC for measurement and monitoring, a suite of advanced and general-purpose timers, and multiple serial interfaces (USART/UART, SPI/I2S, I2C). Operating from 1.7 V to 3.6 V over a -40°C to +85°C temperature range (T6 grade), the STM32F446RET6 is designed to serve in industrial control, IoT nodes, instrumentation, motor control, and other embedded applications where reliable performance matters.

At a glance

• Brand and series: STMicroelectronics STM32F4
• MPN: STM32F446RET6 (LQFP-64, 10×10 mm, 0.5 mm pitch)
• Core: ARM Cortex-M4F with single-precision FPU and DSP extensions
• Frequency: Up to 180 MHz
• Memory: 512 KB Flash, ~128 KB SRAM
• Peripherals: USB 2.0 Full-Speed OTG, bxCAN, 12-bit ADC, timers, USART/UART, SPI/I2S, I2C
• Operating range: 1.7 V to 3.6 V, -40°C to +85°C (T6)
• Mounting/package: Surface-mount, LQFP-64; packaging: Tray (tape-and-reel variant STM32F446RET6TR)
• Lifecycle: Active; RoHS and REACH compliant

Key specifications

Core and performance

• CPU core: ARM Cortex-M4F (with FPU)
• Architecture: 32-bit ARM
• Max clock speed: Up to 180 MHz
• DSP/FPU: Single-precision floating-point unit and DSP extensions

Memory

• Flash memory: 512 KB
• SRAM: ~128 KB

Connectivity and peripherals

• Digital interfaces: USART/UART, SPI/I2S, I2C
• USB: USB 2.0 Full-Speed OTG
• CAN: bxCAN interface
• Timers: Advanced and general-purpose timers
• Analog: 12-bit ADC
• I/O: 5 V tolerant on select pins (per datasheet guidance)

Electrical and environmental

• Operating voltage (VDD): 1.7 V to 3.6 V
• Temperature range (T6): -40°C to +85°C
• ESD: ESD protection on I/Os (per datasheet)

Package and mounting

• Package: LQFP-64, 10×10 mm, 0.5 mm pitch
• Mounting type: Surface Mount
• Packaging: Tray (ordering option STM32F446RET6TR for tape-and-reel)

Peripherals and subsystem highlights

Processing headroom with Cortex-M4F

The STM32F446RET6 leverages the ARM Cortex-M4F core to accelerate math-heavy tasks often found in control loops, filtering, and sensing. The combination of single-precision FPU and DSP instructions reduces CPU cycles for multiply–accumulate, trigonometric approximations, and statistical routines, freeing time for application logic and I/O management.

Rich digital communication options

Multiple serial ports (USART/UART) support command-and-control links, bootloaders, and wired field communications. SPI/I2S enables fast register access to sensors and expands to audio streaming with I2S framing. I2C rounds out the low-pin-count bus options for EEPROMs, sensors, and peripheral controllers. This mix allows designers to partition bandwidth-sensitive, control, and management data across appropriate buses.

USB 2.0 Full-Speed OTG flexibility

With integrated USB 2.0 Full-Speed OTG, the STM32F446RET6 can operate as a device, a host, or in OTG roles. This enables designs ranging from USB peripherals and data loggers to simple host-based accessories. FS bandwidth is well-suited for command/control and moderate data transfer without the complexity of high-speed PHYs.

bxCAN for reliable networking

The bxCAN peripheral provides a durable fieldbus option for industrial control, robotics, and automotive-adjacent applications that rely on CAN’s arbitration, error handling, and deterministic bus behavior. It is a natural fit for distributed control, sensor fusion over CAN, and gateway applications bridging to other serial interfaces in the system.

Timing and control

Advanced and general-purpose timers provide the backbone for precision control, PWM generation, input capture, and timebase creation. Whether synthesizing motor drive PWMs or scheduling periodic tasks, the timer set supports tight loop control and synchronization with other peripherals.

Analog measurement

A 12-bit ADC enables sampling of sensors, supplies, and control signals, supporting closed-loop systems and monitoring tasks. Combined with the DSP capabilities of the Cortex-M4F, designers can implement filtering and signal conditioning directly on the MCU.

Electrical and environmental ratings

• Supply voltage: 1.7 V to 3.6 V operating range
• Temperature: -40°C to +85°C (T6 grade)
• I/O tolerance: 5 V tolerant on select pins (refer to datasheet for eligible pins and conditions)
• ESD: Integrated protection on I/Os (details per datasheet)

These ratings make the STMicroelectronics STM32F446RET6 a straightforward choice for battery-powered devices (operating at 3.3 V rails) and industrial controllers alike. The extended temperature range helps ensure performance across typical ambient extremes for embedded deployments.

Packaging, ordering, and handling

• Package: LQFP-64
• Body size and pitch: 10×10 mm, 0.5 mm lead pitch
• Mounting: Surface Mount
• Standard packing: Tray
• Tape-and-reel option: STM32F446RET6TR

The 64-pin LQFP format balances solderability and routing density. With 0.5 mm pitch and a modest footprint, it’s suitable for four-layer boards common in control and instrumentation designs. The Tray option serves low-to-mid volume assembly, while the STM32F446RET6TR variant supports automated high-volume SMT with tape-and-reel packaging. Always follow standard handling practices for moisture-sensitive devices and ESD protection as indicated in the official documentation.

Applications and design fit

• Industrial control and automation
• Consumer and handheld devices
• IoT and connected sensors
• Motor control and drivers
• Instrumentation and data acquisition

The STM32F446RET6’s fast core and DSP/FPU support make it especially adept at real-time control tasks where deterministic behavior and numerical efficiency are important. The bxCAN interface enables distributed control over robust cabling, while USB FS OTG supports direct PC connectivity, mass-storage style logging, or simple host functions. Designers can leverage the 12-bit ADC and timers for motor current sensing, PWM generation, and feedback control loops, with the compute headroom to run signal processing algorithms on the MCU itself.

For portable or battery-powered equipment, operation down to 1.7 V VDD provides flexibility in power management. The broad temperature rating and ESD-protected I/Os suit harsh environments where reliability is a must.

Lifecycle, availability, and sourcing

• Lifecycle status: Active (per STMicroelectronics)
• Availability: Subject to supply; check distributors for current stock
• Current listing inventory: 0 units (no on-hand stock indicated)
• Pricing: Varies by quantity and packaging; consult authorized distributors
• Ordering note: Tape-and-reel variant is STM32F446RET6TR

Sourcing managers evaluating risk can take confidence from the STM32F4 family’s wide adoption and the device’s Active lifecycle status. For second-source planning, consider the guidance below on alternates.

Replacements and approved alternates

• Official replacements: None specified
• Approved alternates policy: Consider pin-compatible STM32F4 devices with the same pin count and voltage range if functionality and performance match. Always verify peripheral availability and memory sizes before substituting.

Because peripheral counts and exact feature sets vary within the STM32F4 family, cross-check your specific needs—interface availability, ADC usage, memory requirements—against each candidate’s datasheet before committing to a drop-in.

Compliance and environmental

• RoHS: RoHS compliant, Pb-free
• REACH: REACH compliant
• ESD: ESD protection on I/Os (per datasheet)

The STM32F446RET6 is suitable for designs targeting global markets with typical environmental compliance expectations. If your application requires detailed materials declarations or certificates, obtain the latest compliance documents from STMicroelectronics or authorized channels.

Design and integration notes

While every design is unique, the following considerations can help you extract maximum value from the STMicroelectronics STM32F446RET6:

• Plan pin multiplexing early. With a rich set of interfaces on a 64-pin device, mapping UARTs, SPI/I2S, I2C, timers, and ADC channels to pins that also support 5 V tolerance where needed helps avoid last-minute reroutes.
• Use the Cortex-M4F’s FPU and DSP instructions for control loops and filtering. Offloading math to hardware extensions reduces latency and frees CPU time for I/O and application logic.
• For USB FS OTG designs, factor connector, cable, and power role (device/host/OTG) choices early. Ensure the board provides proper power switching and protection appropriate to the intended role.
• For bxCAN networks, select a transceiver suitable for your EMC and distance needs and observe bus topology guidelines. The embedded CAN controller provides a robust foundation once the physical layer is chosen.
• Separate sensitive analog nodes from high-speed digital and PWM signals. The 12-bit ADC benefits from clean reference and thoughtful layout.
• Observe datasheet recommendations for ESD precautions and operating conditions, particularly for 5 V tolerant I/Os.

These practices help ensure first-pass success and stable operation in the field without requiring changes late in the design cycle.

Frequently asked questions (FAQs)

Q: What does the T6 suffix indicate?
A: T6 denotes the LQFP-64 package (10×10 mm, 0.5 mm pitch) and -40°C to +85°C temperature range. The tape-and-reel ordering option adds TR (STM32F446RET6TR).

Q: What is the operating voltage of the STM32F446RET6?
A: 1.7 V to 3.6 V on VDD.

Q: Is there a USB interface?
A: Yes. It integrates a USB 2.0 Full-Speed OTG interface.

Q: What is the CPU core and maximum frequency?
A: ARM Cortex-M4F with FPU, running up to 180 MHz.

Q: How much embedded memory does it include?
A: 512 KB Flash and approximately 128 KB SRAM.

Q: Does the STM32F446RET6 support CAN?
A: Yes. It features a bxCAN interface.

Q: Are any pins 5 V tolerant?
A: Yes, select pins are 5 V tolerant. Refer to the datasheet for eligible pins and usage conditions.

Q: What is the operating temperature range?
A: -40°C to +85°C (T6 grade).

Q: Is the device RoHS and REACH compliant?
A: Yes, it is RoHS compliant (Pb-free) and REACH compliant.

Q: What packaging options are available?
A: The standard package is LQFP-64 shipped in Tray. The STM32F446RET6TR variant is tape-and-reel.

Resources

• Product page: https://www.st.com/en/microcontrollers-microprocessors/stm32f446re.html
• Datasheet: https://www.st.com/en/microcontrollers-microprocessors/stm32f446re.html

Summary

The STMicroelectronics STM32F446RET6 delivers a compelling blend of performance and integration for embedded control, sensing, and connectivity. Its ARM Cortex-M4F core with single-precision FPU and DSP extensions provides ample headroom at up to 180 MHz, while 512 KB of Flash and ~128 KB of SRAM support complex real-time applications. The peripheral set—USB 2.0 FS OTG, bxCAN, 12-bit ADC, timers, and versatile serial interfaces—covers the most common needs in industrial control, IoT, instrumentation, and motor drive applications.

With an Active lifecycle, RoHS/REACH compliance, and availability in a mainstream LQFP-64 package, the STM32F446RET6 is straightforward to source and manufacture. If a direct replacement is ever required, ST offers numerous pin-compatible devices within the STM32F4 family; verify interface and memory needs before substitution. For teams seeking a reliable, high-performance MCU platform without unnecessary complexity, the STM32F446RET6 is a strong candidate that shortens development cycles and streamlines sourcing.