STMicroelectronics BLUENRG-345MC

Overview

BLUENRG-345MC from STMicroelectronics is a programmable Bluetooth® Low Energy 5.2 System-on-Chip integrating an Arm® Cortex®-M0+ core (64 MHz), 256 KB flash, 64 KB RAM, and a dedicated BlueNRG radio coprocessor. It delivers -104 dBm RX sensitivity at 125 kbps (Coded PHY), +8 dBm programmable TX output, and supports 128 concurrent BLE connections - deployed in battery-powered medical sensors and industrial edge nodes requiring long-range, low-latency wireless telemetry.

For engineers reviewing the BLUENRG-345MC datasheet, BLUENRG-345MC pinout, BLUENRG-345MC application, or BLUENRG-345MC equivalent, key selection criteria include its dual-role BLE 5.2 stack support (peripheral/central simultaneously), integrated SMPS for sub-1 µA DEEPSTOP current (1.8 V), hardware AES-128/PKA security accelerators, and QFN32 package with 20 GPIOs (31 5V-tolerant, 28 wake-up capable).

Technical Context

The BLUENRG-345MC implements a partitioned BLE protocol stack: time-critical radio operations (e.g., packet timing, Coded PHY decoding, advertising extensions) are offloaded to a DMA-based BlueNRG core coprocessor, while non-real-time tasks (GATT caching, L2CAP channel management) run on the Cortex-M0+. Its RF subsystem uses a low-IF receiver architecture with integrated balun and supports external PA via dedicated RF pins.

Power architecture includes a programmable SMPS (1.2–1.9 V output), dual LDOs (MLDO/LPREG), and three voltage domains (VDD33, VDD12o, VDD12i) enabling granular retention control - SRAM0 retained in DEEPSTOP, others configurable; RTC and IWDG remain active with LSE/LSI clock sources. Wake-up sources include radio timer, RTC alarm, and up to 28 GPIOs.

Key Specifications

Pinout & Package

BLUENRG-345MC is housed in a VFQFPN32 (5 × 5 mm) package with 32-pin layout, exposing 20 general-purpose I/Os, dedicated RF antenna interface (RF_OUT/RF_IN), integrated balun connections, and separate analog/digital ground planes (VSSRF/VSS). Exposed pad must be connected to ground for thermal and RF performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Bluetooth Low Energy SoC applications.

Compared with nRF52840 and CC2642R, BLUENRG-345MC uniquely combines Coded PHY range extension, integrated SMPS for single-digit µA deep sleep, and PKA-accelerated ECDH - making it optimal for certified medical wearables and industrial battery nodes where regulatory compliance and multi-year runtime are non-negotiable.

Availability

BLUENRG-345MC is available at Aetrix Electronics and suitable for industrial sensor nodes, wireless medical patches, smart lighting controls, and asset tracking tags requiring stable component supply across extended product lifecycles.

Supply support for BLUENRG-345MC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, MEMS sensors, and wireless SoCs for industrial, automotive, and consumer markets.

The BlueNRG-LP product line targets ultra-low-power wireless edge devices - engineered specifically for battery-operated BLE 5.2 applications demanding >10-year runtime, industrial temperature resilience, and hardware-enforced security certification paths.

FAQ

What package variants does BLUENRG-345MC support?

BLUENRG-345MC is exclusively offered in the VFQFPN32 (5 × 5 mm) package with 32 pins and an exposed thermal pad. This variant provides 20 GPIOs, supports all BLE 5.2 features, and is pin-compatible with other BlueNRG-LP QFN32 derivatives like BLUENRG-345A. The WLCSP49 and VFQFPN48 variants are separate order codes (e.g., BLUENRG-345V, BLUENRG-345M) and not interchangeable.

Does BLUENRG-345MC require an external crystal oscillator?

Yes - BLUENRG-345MC requires a 32 MHz external crystal for main system clock and a 32 kHz crystal for RTC/low-power timing. Both oscillators include integrated trimming capacitors, eliminating external load capacitors. The internal 32 kHz RO oscillator is available as a backup but lacks the ±20 ppm accuracy needed for BLE advertising interval compliance.

How is Bluetooth stack licensing handled for BLUENRG-345MC?

STMicroelectronics provides the complete BLE 5.2 protocol stack (including host/controller layers) royalty-free with the BlueNRG-LP SDK. No additional Bluetooth SIG membership or qualification fees are required for end-product certification. Stack source code is available under NDA, and pre-certified stack binaries are included for FCC/CE/IC regulatory testing.

Can BLUENRG-345MC operate as both BLE central and peripheral simultaneously?

Yes - BLUENRG-345MC supports true concurrent dual-role operation: it can maintain up to 128 connections as a peripheral while simultaneously acting as a central managing up to 32 connected sensors. This is enabled by hardware partitioning between the BlueNRG coprocessor (radio timing) and Cortex-M0+ (stack logic), verified in ST's AN5471 application note.