STM32L433CCU3 - 80MHz Cortex-M4 MCU | STMicroelectronics
MPN: STM32L433CCU3 ✓ ActiveSTM32L433CCU3 Overview
A microcontroller is a programmable semiconductor that integrates a processor core, memory, peripherals, and interface logic into one compact device. The STM32L433 belongs to the STM32L4 family of 32-bit RISC microcontrollers, where its Cortex-M4 core combines efficient control processing with floating-point and DSP instruction support. This hierarchy places the device between general-purpose embedded processors and highly integrated application-specific controllers.
Principal features include 256 KB of Flash for firmware and data, 64 KB of SRAM for working memory, an Arm Cortex-M4 FPU, 100 DMIPS processing performance, and a maximum clock frequency of 80 MHz. USB full-speed support enables USB connectivity, while the integrated LCD controller serves compact human-interface designs. The external SMPS capability can support efficient power management in low-power embedded systems.
The STM32L433 architecture is suited to connected control systems where processing performance, memory capacity, and low-power operation must coexist within a small package. Its Cortex-M4 core executes single-precision floating-point and DSP instructions, while the STM32L4 family peripherals consolidate communication, timing, analog, and debug functions around the processor. The 48-pin UFQFPN package supports compact board layouts without using a large leaded package.
Typical applications include USB-connected data acquisition, compact industrial control modules, low-power sensor gateways, human-interface panels with an LCD, secure or connected embedded controllers, and portable measurement equipment. The combination of 80 MHz processing and 256 KB Flash is especially useful for protocol handling, local data processing, and firmware-intensive control tasks.
Designers should confirm the pin configuration, supported voltage combinations, clock setup, and peripheral assignment against the manufacturer datasheet before schematic capture. PCB planning must preserve access to the exposed pad, programming and debug interfaces, and all power pins. Firmware should also use the STM32CubeMX or STM32CubeIDE device configuration tools when creating clock trees and peripheral initialization sequences.
This page combines the manufacturer specifications, package and memory details, practical application guidance, drop-in alternatives, and design considerations needed to evaluate the STM32L433CCU3 for a new embedded product. It also highlights where a different STM32L4 member may be preferable when memory size, qualification, or extended features differ.
Drop-in alternatives for STM32L433CCU3 — 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 STM32L433CCU3 (same form factor and footprint) — differing in Processor Core, Product Type, Backup Registers.
STM32L433CCU6
✅ Drop-InContact for price
View Datasheet →STM32L433CBU6
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STM32L431CCU6
✅ Drop-In📋 Reference alternative (not in catalog)
STM32L432CCU6
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STM32L443CCU6
✅ Drop-InContact for price
View Datasheet →STM32L433CCU3 Maximum Ratings & Electrical Characteristics
| Product Type | 32-bit ultra-low-power microcontroller |
| Processor Core | Arm Cortex-M4 with single-precision FPU |
| Maximum CPU Frequency | 80 MHz |
| Peak Core Performance | 100 DMIPS |
| Flash Memory | 256 KB |
| SRAM | 64 KB |
| Program Memory Architecture | 256K x 8 bits |
| USB Interface | USB full-speed |
| Display Support | LCD controller |
| Power Supply Architecture | External SMPS |
| Supply Voltage Options | 1.8 V, 2.5 V, or 3.3 V |
| Package | 48-pin UFQFPN, 7 x 7 mm |
| Mounting Type | Surface mount |
| Shipping Format | Tray |
| DSP Instruction Support | Supported by Arm Cortex-M4 core |
| Architecture | 32-bit RISC |
STM32L433CCU3 48-pin ufqfpn, 7 x 7 mm Pin Configuration Guide
Pin configuration for STM32L433CCU3 (48-pin 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 STM32L433CCU3.
Refer to the datasheet for full pin configuration.
Typical Applications
STM32L433CCU3 is suitable for 6 applications: USB Connected Data Acquisition, Industrial Sensor Gateway, Low-Power Environmental Monitor, Compact LCD Control Panel, Portable Measurement Instrument, Secure Connected Controller.
USB Connected Data Acquisition
The STM32L433CCU3 fits compact data-acquisition equipment because its Arm Cortex-M4 core operates up to 80 MHz while USB full-speed provides a direct device connection. The 256 KB of Flash can hold acquisition firmware, calibration tables, and USB descriptors, and 64 KB of SRAM supports sample buffers and working state. Use the MCU to sample sensors, format results, and expose them through USB without a separate interface controller. Validate USB impedance routing, connector protection, power sourcing, and enumeration behavior in the final board design.
Recommended
Industrial Sensor Gateway
The STM32L433CCU3 is appropriate for industrial sensor gateways that need local processing between a sensor interface and an upstream network. Its 80 MHz Cortex-M4 processor and 100 DMIPS performance allow protocol conversion, filtering, and device management in one low-power controller. The 256 KB Flash accommodates application firmware while 64 KB of SRAM handles queues and protocol state. For deployments using Ethernet, a companion LAN8742 interface can add network connectivity, but the UART, I2C, or SPI implementation must be matched to the selected gateway architecture.
Recommended
Low-Power Environmental Monitor
The ultra-low-power STM32L4 architecture makes STM32L433CCU3 suitable for battery-operated environmental monitors that periodically measure sensors and transmit results. Its low-power operating modes can reduce average consumption between readings, while the Cortex-M4 core performs compensation and filtering without requiring a higher-power processor. External SMPS support can help implement an efficient multi-rail design. A typical system would use I2C or SPI sensors, store calibration data in Flash, and wake the MCU on a timer or sensor event before reporting through USB or another communication interface.
Recommended
Compact LCD Control Panel
The STM32L433CCU3 supports compact human-interface panels because it combines an LCD controller with an 80 MHz Cortex-M4 core in a 48-pin UFQFPN package. The processor can drive graphical updates, manage user input, and execute application logic while USB full-speed provides configuration or service connectivity. Its 256 KB Flash and 64 KB SRAM allow a meaningful local interface without requiring a separate display controller. LCD timing, panel bias requirements, backlight power, contrast control, and interface voltage must be designed around the electrical characteristics in the manufacturer datasheet.
Recommended
Portable Measurement Instrument
The STM32L433CCU3 works well in portable measurement instruments where a high-performance MCU, local memory, USB connectivity, and compact packaging are valuable. The Cortex-M4 FPU accelerates single-precision calculations, while DSP instructions support filtering and signal conditioning. Firmware can combine acquisition control, calibration, data processing, and USB communication within the 256 KB Flash and 64 KB SRAM limits. Analog front-end design remains separate from the MCU, so input ranges, sampling architecture, grounding, shielding, and reference accuracy should be established independently before assigning the MCU pins.
Recommended
Secure Connected Controller
The STM32L433CCU3 can serve as the central controller in compact connected equipment that requires secure firmware handling and flexible serial communications. Its 256 KB Flash and 64 KB SRAM support an RTOS, communication stacks, and application code, while the 80 MHz core leaves headroom for local control tasks. If cryptographic hardware or stronger security features are required, STM32L443CCU6 may be the more appropriate member of the pin-compatible STM32L4 family. Final security decisions should include boot configuration, key protection, update mechanisms, and production provisioning requirements.
Recommended
Recommended Products Summary
Engineering reference data for STM32L433CCU3 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | STM32L433CCU6 | STM32L433CBU6 | STM32L431CCU6 | STM32L432CCU6 | STM32L443CCU6 |
|---|---|---|---|---|---|---|
| Package | 48-UFQFPN (7x7) | 48-UFQFPN (7x7) | 48-UFQFPN (7x7) | 48-UFQFPN (7x7) | 48-UFQFPN (7x7) | 48-UFQFPN (7x7) |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Processor Core | Arm Cortex-M4 with FPU | Arm Cortex-M4 with FPU | Arm Cortex-M4 with FPU | Arm Cortex-M4 with FPU | Arm Cortex-M4 with FPU | Arm Cortex-M4 with FPU |
| Maximum CPU Frequency | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 80 MHz | 80 MHz |
| Core Performance | 100 DMIPS | 100 DMIPS | 100 DMIPS | 100 DMIPS | 100 DMIPS | 100 DMIPS |
Key Differentiators
- Higher program-memory capacity than the B-density family alternative (vs STM32L433CBU6)
- USB and LCD integration in one compact microcontroller (vs STM32L431CCU6)
- External SMPS support for multi-rail low-power designs (vs STM32L432CCU6)
- Broader security-oriented feature option within the same footprint (vs STM32L433CCU6)
Design Notes
Allocate the 48-pin UFQFPN footprint directly from the manufacturer land-pattern drawing and preserve thermal-pad access under the device. Place all supply pins and their decoupling capacitors close to their respective pins, with short, low-loop connections between each capacitor and the associated power terminal. The exposed pad should be connected according to the datasheet's power and thermal guidance, while watch, solder-mask, and paste volumes must be checked against the assembly process to avoid voiding or pad detachment.
Select the supply arrangement from the stated 1.8 V, 2.5 V, or 3.3 V options after confirming the complete internal and external peripheral configuration. Decouple each active supply domain independently and verify startup, shutdown, and current transitions against the electrical limits in the manufacturer datasheet. If the external SMPS path is used, analyze its efficiency and sequencing together with the MCU rather than treating it as an independent regulator function. Include brownout behavior in the firmware and power-supply design.
Route USB differential pairs as a controlled-impedance pair on a continuous reference plane, minimize stub branches, and place the USB connector protection and routing according to the selected USB implementation. Keep the 80 MHz clock and sensitive analog inputs away from high-current switching and USB return currents. Assign debug and programming pins early in the schematic because their alternate-function options may constrain the final pin map. Review every alternate function against the configured peripheral rather than relying only on the package drawing.
Do not treat an STM32L4 family member with the same package as automatically interchangeable. Verify the exact order code, temperature range, Flash capacity, SRAM, LCD controller, USB implementation, external SMPS availability, and security features. A 128 KB Flash alternative such as STM32L433CBU6 requires a firmware-size check, while reduced-feature L431 and L432 variants may lack functions assumed by the original design. Complete a bootloader, peripheral, brownout, and pin-level review before releasing a substitution to production.
Compliance Information
Compliance status was not stated in the manufacturer or product-page material used for this record. Confirm RoHS, REACH, AEC-Q100, lead-free, halogen-free, and conflict-minerals requirements for the exact order code and shipment configuration before production release.