STM32L451CEU6 - 80MHz Cortex-M4 MCU 512KB Flash | STMicroelectronics
N.º da peça: STM32L451CEU6 ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $9.8 | $9,80 |
| 10 | $8.65 | $86,50 |
| 100 | $7.42 | $742,00 |
| 500 | $6.55 | $3.275,00 |
| 1.000 | $5.95 | $5.950,00 |
STM32L451CEU6 Visão geral
An ultra-low-power microcontroller (MCU) is a class of 32-bit microcontroller optimized for battery-powered and energy-harvesting systems where average current draw over sleep-active duty cycles is the dominant design constraint. Within the broader taxonomy, the STM32L4 sits between general-purpose Cortex-M4 MCUs and the lower-power Cortex-M0+ families, occupying the ultra-low-power branch alongside the Cortex-M33 STM32L5 and Cortex-M0+ STM32L0. Its FPU and DSP extensions place it above M0+ parts in compute density, while its multi-domain power architecture (separate Core, peripheral, and memory voltage domains) places it above classical Cortex-M4 in energy efficiency.
Key differentiating specifications include the 80 MHz Cortex-M4 core with single-precision FPU and DSP instructions, 1.71 V to 3.6 V operating supply range, five low-power modes (Sleep, Low-Power Sleep, Stop 0/1/2, Standby, Shutdown) with Shutdown current under 30 nA typical, and an integrated 12-bit ADC with hardware oversampling. The device also provides two DAC channels, three I2C, three SPI, one CAN 2.0B, one USB 2.0 Full-Speed device/host, and an integrated DFSDM digital filter for sigma-delta modulation.
Architecturally, the STM32L451CEU6 uses ST's 90 nm ultra-low-leakage process with an adaptive voltage scaling loop that scales the core domain between 1.0 V and 1.2 V based on operating frequency. This allows RUN-mode current to track load and yields approximately 100 uA/MHz active efficiency. The 160 KB SRAM is split into multiple independent banks to allow retention-only sleep configurations that keep selected peripherals alive while the core domain is powered down.
Typical applications include wearable health monitors, battery-powered sensor hubs, industrial 4-20 mA loop-powered transmitters, smart metering, BLE/Zigbee host controllers, and low-end audio processing using the on-board DFSDM. The 48-pin UFQFPN package is the right density point for designs needing CAN or USB plus a 12-bit analog front-end without paying for the larger 64-pin variants.
When designing with this device, prioritize decoupling close to each VDD pin pair (one 100 nF X7R per domain plus one 4.7 uF bulk) and respect the UFQFPN exposed-pad solder process to keep junction temperature rise within datasheet limits. The Cortex-M4 FPU is single-precision only - use double-precision math in firmware will trap.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Alternativas drop-in para STM32L451CEU6 — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com STM32L451CEU6 (mesmo formato e footprint) — diferindo em ADC, DAC, Package, SRAM, Shutdown Current.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
STM32L452CEU6
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
STM32L433CCU6
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
STM32L412CBU6
✅ Drop-In✓ Em estoque
$2.74 / unidade
Ver ficha técnica →STM32L431CBU6
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
STM32L451CEU6 Classificações máximas e características elétricas
| Core | ARM Cortex-M4 with FPU and DSP |
| Frequência máxima de clock | 80 MHz |
| Flash Memory | 512 KB |
| SRAM | 160 KB |
| Operating Voltage Range | 1.71 V to 3.6 V |
| Encapsulamento | 48-pin UFQFPN (7x7 mm) |
| Tipo de montagem | Surface Mount |
| Corrente de desligamento | 30 nA typical |
| Temperatura de operação | -40C to +85C |
| ADC | 12-bit, up to 5 Msps, hardware oversampling |
| DAC | 2 channels, 12-bit |
| USB | USB 2.0 Full-Speed device/host |
| CAN | 1x CAN 2.0B |
| I2C Interfaces | 3 |
| SPI Interfaces | 3 |
| DFSDM | Yes (digital filter for sigma-delta modulators) |
| Status RoHS | Compliant |
Configuração de pinos do STM32L451CEU6
| Pino 1 | PB8 — GPIO/TIM4_CH3/I2C1_SCL (alternate functions) |
| Pino 2 | PB9 — GPIO/TIM4_CH4/I2C1_SDA (alternate functions) |
| Pino 3 | VDD — Main digital supply 1.71-3.6 V |
| Pino 4 | VSS — Digital ground |
| Pino 5 | VDDA — Analog supply (ADC/DAC) |
| Pino 6 | VREF+ — ADC positive reference voltage |
| Pino 7 | PA0 — GPIO/ADC_IN0/TIM2_CH1 |
| Pino 8 | PA1 — GPIO/ADC_IN1/TIM2_CH2 |
| Pino 9 | PA2 — GPIO/USART2_TX/ADC_IN2 |
| Pino 10 | PA3 — GPIO/USART2_RX/ADC_IN3 |
| Pino 11 | PA4 — GPIO/SPI1_NSS/DAC_OUT1 |
| Pino 12 | PA5 — GPIO/SPI1_SCK/DAC_OUT2 |
| Pino 13 | PA6 — GPIO/SPI1_MISO/ADC_IN6 |
| Pino 14 | PA7 — GPIO/SPI1_MOSI/ADC_IN7 |
| Pino 15 | PB0 — GPIO/ADC_IN8/TIM3_CH3 |
| Pino 16 | PB1 — GPIO/ADC_IN9/TIM3_CH4 |
| Pino 17 | PB2 — GPIO/BOOT1 |
| Pino 18 | VSS — Digital ground |
| Pino 19 | VDD — Main digital supply 1.71-3.6 V |
| Pino 20 | PA8 — GPIO/TIM1_CH1/MCO |
| Pino 21 | PA9 — GPIO/USART1_TX/I2C1_SCL |
| Pino 22 | PA10 — GPIO/USART1_RX/I2C1_SDA |
| Pino 23 | PA11 — GPIO/USB_DM/CAN1_RX |
| Pino 24 | PA12 — GPIO/USB_DP/CAN1_TX |
| Pino 25 | PA13 — GPIO/SWDIO (debug data) |
| Pino 26 | VSS — Digital ground |
| Pino 27 | VDD — Main digital supply 1.71-3.6 V |
| Pino 28 | PA14 — GPIO/SWCLK (debug clock) |
| Pino 29 | PA15 — GPIO/SPI3_NSS/TIM2_CH1 |
| Pino 30 | PB3 — GPIO/SPI3_SCK/TIM2_CH2 |
| Pino 31 | PB4 — GPIO/SPI3_MISO/TIM3_CH1 |
| Pino 32 | PB5 — GPIO/SPI3_MOSI/TIM3_CH2 |
| Pino 33 | PB6 — GPIO/USART1_TX/I2C1_SCL |
| Pino 34 | PB7 — GPIO/USART1_RX/I2C1_SDA |
| Pino 35 | PH0 — OSC_IN (external crystal) |
| Pino 36 | PH1 — OSC_OUT (external crystal) |
| Pino 37 | VSS — Digital ground |
| Pino 38 | VDD — Main digital supply 1.71-3.6 V |
| Pino 39 | PC13 — GPIO/RTC_TAMP1/RTC_OUT |
| Pino 40 | PC14 — GPIO/OSC32_IN (LSE crystal) |
| Pino 41 | PC15 — GPIO/OSC32_OUT (LSE crystal) |
| Pino 42 | VBAT — RTC backup supply |
| Pino 43 | PA0 — GPIO/WKUP1/ADC_IN0 |
| Pino 44 | NRST — Reset input (active low) |
| Pino 45 | BOOT0 — Boot mode select |
| Pino 46 | PB10 — GPIO/I2C2_SCL/USART3_TX |
| Pino 47 | PB11 — GPIO/I2C2_SDA/USART3_RX |
| Pino 48 | VSS — Digital ground (exposed pad) |
Aplicações típicas
STM32L451CEU6 é adequado para 6 aplicaçãos: Wearable Health Monitor, Industrial 4-20 mA Loop-Powered Sensor, Smart Electricity Meter, BLE/Zigbee Sensor Hub Host Controller, Audio Processing with PDM Microphones, Battery-Powered IoT Edge Node.
Wearable Health Monitor
The STM32L451CEU6's sub-30 nA Shutdown current and 160 KB SRAM retention make it ideal for battery-powered wearables that must run heart-rate or SpO2 algorithms while sleeping most of the time. Its 80 MHz Cortex-M4 with FPU processes PPG and ECG DSP filters in single-precision math without overflowing battery budget, while the 12-bit ADC at up to 5 Msps captures photodiode signals from optical sensors. Compared with discrete ADC + low-power MCU combinations, the L451 collapses two parts into one, shrinking the BOM for wrist-worn form factors.
Recomendado
Industrial 4-20 mA Loop-Powered Sensor
Loop-powered 4-20 mA transmitters extract 3.6 mA at minimum, leaving tight current headroom for the MCU. The STM32L451CEU6's 1.71 V minimum supply lets it run from the loop voltage even when current is at the 3.6 mA lower bound, while its Stop 2 mode at under 1 uA leaves virtually all loop current for the sensor itself. The 12-bit ADC with hardware oversampling reaches 16-bit effective resolution for precise bridge-sensor readout, and the integrated DAC can drive the 4-20 mA output stage directly.
Recomendado
Smart Electricity Meter
Smart meters demand simultaneous metrology accuracy and low standby draw, which the STM32L451CEU6 addresses with its dual 12-bit ADC channels and DFSDM peripheral for direct connection to shunt current sensors. The 512 KB Flash holds the metering firmware plus DLMS/COSEM communication stacks, and the 160 KB SRAM keeps TCP/IP and TLS handshake state resident during metering cycles. According to ST reference designs, the L4 family's 100 uA/MHz RUN efficiency lets metrology run continuously while staying within IEC 62053-21 power budgets.
Recomendado
BLE/Zigbee Sensor Hub Host Controller
When used as the application processor behind a BLE or Zigbee radio module, the STM32L451CEU6 runs ZephyrOS or FreeRTOS while its Cortex-M4 FPU processes sensor-fusion data before wireless transmission. The USB 2.0 Full-Speed controller supports DFU bootloader mode for field firmware updates, and the three SPI buses interface to radios, sensors, and external Flash simultaneously. Stop 2 mode with full SRAM retention lets the hub sleep between sensor events while preserving network context.
Recomendado
Audio Processing with PDM Microphones
The STM32L451CEU6's DFSDM peripheral accepts PDM bit-streams from digital MEMS microphones and converts them to PCM at 16 kHz / 48 kHz sample rates, offloading the CPU entirely. The two integrated 12-bit DACs can drive Class-D amplifier PWM or generate line-level audio outputs for intercom panels. Compared with adding an external audio codec, the L451 solution saves $1-2 BOM and ~50 mm^2 board area, while its 160 KB SRAM holds 100 ms of audio buffer at 16 kHz without spilling to external memory.
Recomendado
Battery-Powered IoT Edge Node
Edge nodes running TensorFlow Lite Micro or similar on-device ML inference benefit from the STM32L451CEU6's 80 MHz Cortex-M4 with single-precision FPU, which executes typical keyword-spotting or anomaly-detection models in single-digit milliseconds. Its 1.71 V minimum supply enables direct LiSOCl2 primary cell operation down to the cut-off voltage, while Stop 2 mode at under 1 uA preserves model weights in retention SRAM. The CAN 2.0B controller supports industrial bus protocols for predictive-maintenance deployments.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para STM32L451CEU6 — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | STM32L452CEU6 | STM32L433CCU6 | STM32L412CBU6 | STM32L431CBU6 |
|---|---|---|---|---|---|
| Package | UFQFPN-48 (7x7 mm) | UFQFPN-48 (7x7 mm) - same | UFQFPN-48 (7x7 mm) - same | UFQFPN-48 (7x7 mm) - same | UFQFPN-48 (7x7 mm) - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Core / Max Clock | Cortex-M4 / 80 MHz | Cortex-M4 / 80 MHz | Cortex-M4 / 80 MHz | Cortex-M4 / 80 MHz | Cortex-M4 / 80 MHz |
| Flash Memory | 512 KB | 512 KB | 256 KB (-50%) | 128 KB (-75%) | 128 KB (-75%) |
| SRAM | 160 KB | 160 KB | 64 KB (-60%) | 40 KB (-75%) | 64 KB (-60%) |
| AES-256 / TRNG | No | Yes (AES-256 + TRNG) | No | No | No |
| DFSDM | Yes | Yes | Yes | No | No |
| USB / CAN | USB FS + CAN 2.0B | USB FS + CAN 2.0B | USB FS + CAN 2.0B | USB FS only | USB FS only |
| Approx. Unit Price (qty 1000) | $5.95 | $6.50 (est.) | $4.95 (est.) | $3.20 (est.) | $3.80 (est.) |
Principais diferenciais
- Highest Flash/SRAM density in 48-pin UFQFPN STM32L4 family (vs STM32L412CBU6)
- AES-256 and TRNG absent on L451 but present on upgrade path (vs STM32L452CEU6)
- Integrated DFSDM for direct digital microphone interface (vs STM32L431CBU6)
- USB 2.0 Full-Speed device/host with internal pull resistors (vs STM32L433CCU6)
Notas de projeto
Each VDD pin pair on the STM32L451CEU6 requires its own 100 nF X7R decoupling capacitor placed within 2 mm of the pin, plus one shared 4.7 uF bulk capacitor near the package. According to ST AN4588, the UFQFPN48's lead inductance causes ringing above 50 MHz if the decoupling loop is too long - keep the 100 nF vias directly under the package balls when possible. Estimated: total decoupling budget is approximately 6 capacitors and 8.4 uF of bulk capacitance for the entire IC.
The UFQFPN48 package has a theta_JA around 35 C/W on a 4-layer JEDEC test board, with the exposed pad carrying the dominant thermal path. According to ST AN5036, the center pad must be soldered to a copper area of at least 50 mm^2 with thermal vias to the inner/inner planes - otherwise junction temperature can rise above 100 C at moderate workloads. Estimated: at full 80 MHz Cortex-M4 + ADC activity (~30 mA total), the junction temperature rise is about 25 C above ambient on a properly stitched board.
Route the USB DP/DM pair (PA11/PA12) as a 90-ohm differential pair with no stubs, length-matched within 150 mils. According to ST AN4871, the crystal traces (PH0/PH1 for HSE, PC14/PC15 for LSE) must be kept short and guarded by a ground ring, with capacitance loading below 10 pF total to keep oscillator start-up margin safe. Place the HSE crystal within 5 mm of the MCU pins to avoid start-up failures in low-temperature corners.
Do not assume Stop 2 mode preserves all SRAM - the STM32L451CEU6's 160 KB SRAM is split into two power domains, and Stop 2 keeps both banks alive but Standby mode drops them. According to ST AN4621, firmware must reinitialize any retained peripherals' clocks after Stop 2 wake because the peripheral bus resets. Also: the BOOT0 pin must be tied through a 10 kohm pulldown to VSS - a floating BOOT0 prevents normal boot and forces System Memory bootloader.
The DFSDM peripheral on the STM32L451CEU6 is sensitive to clock jitter from the PDM microphone source - keep the PDM clock below 3.25 MHz to stay within the DFSDM's internal filter bandwidth. According to ST UM1856, route PDM data and clock as length-matched pairs with a 33-ohm series termination to suppress reflections on cables longer than 50 mm. For multi-microphone arrays, use the second DFSDM channel and ensure both PDM clocks are tied to the same TIM output to keep sample alignment under 100 ns.
Informações de conformidade
RoHS and REACH compliant per ST material declaration. UFQFPN48 meets JEDEC J-STD-020 MSL3 reflow profile. AEC-Q100 not applicable - the L451 is not an automotive-grade part; for AEC-Q100 qualified equivalents, see STM32L4A6xx or STM32L4P5xx part numbers.
