STM32L4R9AII6U STMicroelectronics Integrated Circuit (BGA) In Stock
The STM32L4R9AII6U is a 32-bit ARM Cortex-M4 ultra-low-power microcontroller from STMicroelectronics featuring up to 120 MHz clock, 2 MB Flash, 640 KB SRAM, and a True Random Number Generator in a BGA package. It targets smart wearables and IoT end nodes requiring high compute performance with minimal battery consumption. Available from global authorized distributors with competitive pricing.
- Manufacturer
- STMicroelectronics
- Package
- BGA
- Pin Count
- 169
- Lifecycle
- ACTIVE
- Datasheet
- STM32L4R9AII6U Datasheet PDF
- Category
- Integrated Circuit
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of STM32L4R9AII6U?
- ARM Cortex-M4 core with FPU running at up to 120 MHz delivers DSP-class signal processing at ultra-low-power consumption for battery-operated IoT and wearable designs
- 2 MB Flash and 640 KB SRAM provide ample on-chip storage for complex firmware, ML inference models, and large sensor data buffers without external memory
- Integrated True Random Number Generator (TRNG), AES-256, and PKA hardware accelerators enable secure IoT communication with TLS/DTLS encryption in low-power standby modes
What is STM32L4R9AII6U used for?
The STM32L4R9AII6U is designed for smart wearable devices, medical health monitors, and industrial IoT sensor nodes that require Cortex-M4 DSP performance with ultra-low active and standby current draw to maximize battery life in coin-cell or small Li-Po powered products. Its 2 MB Flash capacity supports embedded ML frameworks such as STM32Cube.AI for on-device gesture recognition, anomaly detection, and voice keyword spotting without cloud dependency. The integrated hardware security subsystem with AES-256 and PKA also makes it well-suited for secure IoT gateways, asset trackers, and connected medical devices requiring robust firmware protection.
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Where can I find the STM32L4R9AII6U datasheet?
STM32L4R9AII6U Datasheet DownloadOfficial datasheet from STMicroelectronics
What are equivalent replacements for STM32L4R9AII6U?
Compatible alternatives and drop-in replacements for STM32L4R9AII6U:
RISC Microcontroller, 32-Bit, FLASH, CORTEX-M4 CPU, 120MHz, CMOS, PBGA169
RISC Microcontroller, 32-Bit, FLASH, CORTEX-M4 CPU, 120MHz, CMOS, PBGA169
Frequently Asked Questions
What clock frequency and memory size does the STM32L4R9AII6U offer for on-device machine learning inference?
The STM32L4R9AII6U runs the ARM Cortex-M4 core with FPU at up to 120 MHz and provides 2 MB of internal Flash plus 640 KB of SRAM. This combination is sufficient to run STM32Cube.AI compiled neural network models with up to several hundred thousand parameters, achieving inference latencies of under 10 ms for small convolutional networks used in keyword detection or motion classification without external memory.
How does the STM32L4R9AII6U's hardware security engine benefit an IoT connected device compared to software-only encryption?
The integrated AES-256 hardware accelerator processes 128-bit blocks at over 100 MB/s while consuming far less energy than software AES running on the Cortex-M4 core at 120 MHz. The Public Key Accelerator (PKA) handles ECDH and RSA key exchanges in milliseconds rather than seconds, enabling full TLS 1.3 handshakes with under 500 ms latency on constrained IoT links. Hardware isolation of the cryptographic engine also reduces side-channel attack surface compared to pure software implementations.
For a smart wearable design, what package and PCB area does the STM32L4R9AII6U require?
The STM32L4R9AII6U is supplied in a BGA package, which achieves a significantly smaller PCB footprint than equivalent LQFP packages by distributing pads across the die area. BGA mounting requires careful DFM review for via-in-pad or dog-bone fanout strategies, but the overall component area including decoupling capacitors is typically under 100 mm² on a 4-layer board, making it feasible for smartwatch, fitness band, and medical patch form factors.
When should a designer choose the STM32L4R9AII6U over an STM32L4 series device with smaller Flash for an industrial sensor node?
The STM32L4R9AII6U is the right choice when the application firmware plus data storage requirements exceed 512 KB Flash or 128 KB SRAM, which are typical limits of smaller STM32L4 variants. With 2 MB Flash it can hold dual-bank firmware for OTA updates alongside the active image, store 640 KB SRAM data buffers for high-rate ADC logging at 1 MSPS, and run an RTOS with multiple threads without hitting memory constraints that would force an external SPI Flash or SDRAM.
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Why Buy from FindMyChip
About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
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