STM32L422CBU6 - 80MHz Cortex-M4 MCU | STMicroelectronics
MPN: STM32L422CBU6 ✓ ActiveSTM32L422CBU6 Overview
A microcontroller is a programmable system-on-chip used to acquire sensor data, execute control algorithms, manage communications, and supervise peripheral functions. The STM32L4 series sits within the Arm Cortex-M4 microcontroller hierarchy, combining a low-power RISC architecture with integrated memory, communications peripherals, and direct GPIO access. Such devices serve as the central processing elements in sensors, industrial controllers, portable instruments, and connected products.
Key features of the STM32L422CBU6 include an Arm Cortex-M4 core with an FPU, operation up to 80 MHz, 128 KB of embedded flash, and 40 KB of SRAM. The floating-point unit supports efficient arithmetic in control, signal-processing, and sensor-oriented firmware. USB connectivity expands the device's suitability for USB-connected data acquisition, configuration interfaces, and peripheral adapters, while the 48-pin package limits board area without eliminating pin-level customization.
The STM32L422CBU6 is identified as an STM32L422CB variant and belongs to STMicroelectronics' ultra-low-power STM32L4 family. At 80 MHz, the core provides substantially more processing headroom than lower-frequency microcontrollers while retaining a focused embedded feature set. The verified manufacturer datasheet describes an Arm Cortex-M4 processor with FPU, and the product-page search result confirms operation up to 80 MHz. Detailed electrical limits, clock-tree settings, peripheral conditions, and current-consumption figures must be checked in the manufacturer datasheet before final qualification.
Typical uses include low-power sensor nodes, USB data-acquisition devices, compact industrial controllers, portable measurement equipment, and embedded gateways. A design can use the Cortex-M4 FPU for filtering and control calculations, the 128 KB flash for application firmware, and the USB interface for configuration or data transfer. The 7 x 7 mm UFQFPN package also suits space-constrained boards where a smaller alternative in the same family is not required.
Board design should account for all 48 exposed pads, the required support network, decoupling, programming access, clock implementation, and exposed-pad thermal requirements. Verify the exact alternate-pin and exposed-pad assignment against the official STM32L422xx datasheet rather than relying on a generic QFN footprint. Firmware selection, USB peripheral configuration, clock tolerances, and low-power transitions should also be validated together because each affects the final power budget and real-time behavior.
This product record combines verified manufacturer and distributor data, same-package replacement guidance, interface-focused application context, and practical design cautions. It provides a concise engineering reference for comparing the STM32L422CBU6 with related STM32L4 devices while clearly identifying details that require confirmation from the official datasheet.
Drop-in alternatives for STM32L422CBU6 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with STM32L422CBU6 (same form factor and footprint) — differing in Package.
STM32L412CBU6
✅ Drop-InContact for price
View Datasheet →STM32L452CCU6
✅ Drop-In📋 Reference alternative (not in catalog)
STM32L432CBU6
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STM32L442CBU6
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STM32L452CBU6
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STM32L422CBU6 Maximum Ratings & Electrical Characteristics
| Product Type | 32-bit ultra-low-power microcontroller |
| Processor Core | Arm Cortex-M4 with FPU |
| Maximum CPU Frequency | 80 MHz |
| Architecture | 32-bit RISC |
| Flash Memory | 128 KB (128K x 8) |
| SRAM | 40 KB |
| USB Connectivity | Yes |
| Package | 48-UFQFPN (7 x 7 mm) |
| Pin Count | 48 pins |
| Mounting Type | Surface mount |
| Maximum Clock Frequency | 80 MHz |
| Low-Power Feature | Ultra-low-power design |
| Floating-Point Unit | Yes |
STM32L422CBU6 48-ufqfpn (7 x 7 mm) Pin Configuration Guide
Pin configuration for STM32L422CBU6 (48-ufqfpn (7 x 7 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for STM32L422CBU6.
Refer to the datasheet for full pin configuration.
Typical Applications
STM32L422CBU6 is suitable for 6 applications: USB Data-Acquisition Device, Low-Power Sensor Node, Portable Measurement Instrument, Compact Industrial Controller, USB-C Connected Embedded Adapter, Battery-Powered Condition Monitor.
USB Data-Acquisition Device
STM32L422CBU6 fits a compact USB data-acquisition device because it combines an 80 MHz Arm Cortex-M4 core with FPU, 128 KB of flash, 40 KB of SRAM, and verified USB connectivity. The processor can execute sampling control, filtering, and host-interface routines while the USB peripheral handles digital data movement. Compared with a higher-performance application processor, the MCU provides dedicated embedded control with a smaller 48-pin, 7 x 7 mm footprint. The engineering trade-off is finite memory and USB workload capacity, so firmware size, transfer bandwidth, buffering strategy, and USB suspend behavior should be validated against the official datasheet before deployment.
Recommended
Low-Power Sensor Node
The STM32L422CBU6 is suitable for a low-power sensor node that must combine local processing with compactness and expandable connectivity. Its 80 MHz Cortex-M4 core with FPU can perform sensor filtering and compensation calculations, while 128 KB of flash and 40 KB of SRAM support embedded application code and data buffering. The ultra-low-power STM32L4 positioning is useful when the node operates intermittently between battery-powered measurement intervals. USB can provide configuration, diagnostics, or data-retrieval service without requiring a separate communications processor. The principal design requirement is a verified power-budget calculation covering active processing, USB activity, and the selected low-power states.
Recommended
Portable Measurement Instrument
STM32L422CBU6 can serve as the control processor in a portable measurement instrument where an 80 MHz Cortex-M4 with FPU, 128 KB of flash, and 40 KB of SRAM balance processing capability against board area. The floating-point unit assists filter and numerical routines, while the 48-pin UFQFPN package leaves board perimeter for analog, display, and input circuitry. USB connectivity supports data export, configuration, or charging-associated peripheral functions when the complete electrical design supports them. Because the supplied data does not establish the device's analog-performance limits, precision analog front-end specifications must be evaluated separately rather than inferred from the MCU core frequency.
Recommended
Compact Industrial Controller
STM32L422CBU6 is a practical foundation for a compact industrial controller because it combines real-time Cortex-M4 processing up to 80 MHz with 128 KB of embedded flash and a compact 48-pin surface-mount package. The controller can execute state-machine logic, sensor conditioning in firmware, and communication protocols while retaining room for external interface components. Its USB capability can support configuration ports, local service access, or a USB peripheral role. For industrial deployment, engineers must separately verify operating-temperature limits, supply range, isolation requirements, ESD protection, and long-term availability because those properties were not quantified in the supplied source excerpts.
Recommended
USB-C Connected Embedded Adapter
STM32L422CBU6 fits an embedded USB adapter that must combine protocol handling, local control, and firmware storage within a small board. Its 80 MHz Cortex-M4 core with FPU provides processing headroom for packet processing and configuration logic, while 128 KB of flash supports a moderate embedded application and 40 KB of RAM accommodates buffering. The 48-UFQFPN package supports compact layouts, while USB reduces the need for a separate host interface in suitable designs. The main qualification step is checking the exact USB electrical characteristics and pin multiplexing in the manufacturer datasheet, along with the maximum USB power available from the selected connector and supply architecture.
Recommended
Battery-Powered Condition Monitor
STM32L422CBU6 is appropriate for a battery-powered condition monitor that needs periodic sensing, local decision-making, and compact communication. The Cortex-M4 processor can execute threshold logic and digital filters at up to 80 MHz without requiring a separate DSP, while 128 KB of flash stores firmware and calibration tables and 40 KB of SRAM handles short measurement bursts. USB provides an optional service or logging connection when the device is docked. The key engineering requirement is to balance processing speed against average energy use: high-frequency operation may shorten measurement completion but can increase consumption, so low-power mode selection and duty cycle must be based on application-specific measurements.
Recommended
Recommended Products Summary
Engineering reference data for STM32L422CBU6 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | STM32L412CBU6 | STM32L452CCU6 | STM32L432CBU6 | STM32L442CBU6 | STM32L452CBU6 |
|---|---|---|---|---|---|---|
| Package | 48-UFQFPN (7 x 7 mm) | 48-pin PQCC48 class - verify mechanical drawing | 48-pin PQCC48 class - verify mechanical drawing | 48-UFQFPN (7 x 7 mm) family package | 48-UFQFPN (7 x 7 mm) family package | 48-UFQFPN (7 x 7 mm) family package |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| CPU Core | Arm Cortex-M4 with FPU | Arm Cortex-M4 | Arm Cortex-M4 | Arm Cortex-M4 | Arm Cortex-M4 | Arm Cortex-M4 |
| Maximum CPU Frequency | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 80 MHz |
| Architecture | 32-bit RISC | 32-bit RISC | 32-bit RISC | 32-bit RISC | 32-bit RISC | 32-bit RISC |
Key Differentiators
- Verified 128 KB flash and 40 KB SRAM allocation (vs STM32L412CBU6)
- 80 MHz Cortex-M4 processing with FPU (vs STM32L452CCU6)
- Compact 48-pin 7 x 7 mm package (vs STM32L432CBU6)
Design Notes
Do not assign pins from a generic 48-pin QFN symbol. Use the official STM32L422xx package drawing and alternate-pin table to distinguish the exposed ground pad, supply pins, analog-related pins, debug signals, USB pins, and alternate functions. Keep the 7 x 7 mm footprint within the manufacturer's land-pattern and solder-mask recommendations, and verify pin 1 orientation mechanically. This is critical because a footprint-compatible family member can still require PCB or firmware changes.
Build the supply network only after confirming the STM32L422CBU6 operating-voltage range and external decoupling requirements in the manufacturer datasheet. Place required input and output capacitors close to their associated pins, preserve a low-impedance ground return, and isolate analog or sensitive loads from switching nodes. For a USB-connected design, account separately for bus-powered current limits and the device's peak active consumption; the available 80 MHz rating does not by itself establish the acceptable USB power budget.
Treat the UFQFPN exposed pad as a mandatory thermal and electrical connection. Follow the datasheet's land pattern and assembly guidance, provide a low-impedance path to the ground plane, and consider copper spreading where local dissipation is elevated. If the enclosure limits convection, validate the junction-temperature margin using the actual board construction rather than assuming that the compact package remains cool. For battery designs, include temperature effects in the duty-cycle calculation because enclosure and copper area alter heat spreading.
Avoid choosing an alternative solely by the 48-pin count or 80 MHz CPU rating. Compare power pins, exposed-pad requirements, USB routing, clock sources, reset behavior, programming access, RAM, flash, low-power modes, and every peripheral used by the PCB. STM32L412CBU6 and STM32L452CCU6 are verified same-package candidates, but footprint compatibility does not remove the need for firmware and hardware review. Document any substitution with the exact ordering suffix and tested firmware revision.
Compliance Information
The supplied verified excerpts do not provide explicit compliance declarations. Compliance and qualification status must be confirmed on the official STMicroelectronics product page and in the current manufacturer documentation.