STMicroelectronics BLUENRGCSP

Overview

BLUENRGCSP from STMicroelectronics is a Bluetooth Low Energy v4.0-compliant single-mode network processor implementing slave role, featuring an ARM Cortex-M0 core, embedded BLE stack (GAP/GATT/SM/L2CAP/LL/RF-PHY), +8 dBm RF output power, 96 dB link budget, and ultra-low-power operation down to 1.7 μA with active stack-designed for coin-cell-powered wearables like fitness trackers and smart watches.

For engineers reviewing the BLUENRGCSP datasheet, BLUENRGCSP pinout, BLUENRGCSP application, or BLUENRGCSP equivalent, key selection criteria include SPI-based ACI interface compatibility, WLCSP34 package footprint constraints, DC-DC/LDO power management flexibility, RSSI-based transmit power control, and field-upgradable BLE stack stored in on-chip Flash memory.

Technical Context

The BLUENRGCSP integrates a 2.4 GHz BLE radio with full link-layer security (AES-128), a dedicated Cortex-M0 core executing the BLE protocol stack, and dual clocking: 16/32 MHz crystal oscillator (±50 ppm) plus 32 kHz crystal or ring oscillator for low-power timing. It supports both LDO and step-down DC-DC regulation, enabling <10 mA peak TX current at 1 dBm and sub-2 μA deep-sleep current.

Its Application Controller Interface (ACI) uses a 5-wire SPI transport (CS, CLK, MOSI, MISO, IRQ) with hardware handshaking, allowing deterministic host communication while maintaining BLE state autonomy. The device operates across –40 °C to +85 °C and complies with ETSI EN 300 328, FCC Part 15, and ARIB STD-T66.

Key Specifications

Pinout & Package

BLUENRGCSP is housed in a 34-ball WLCSP package (2.66 × 2.56 mm, 0.4 mm pitch), optimized for space-constrained wearable designs. Ball layout follows bottom-view configuration per ST DocID025108 Rev 10 Figure 4.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar BLE network processor applications.

Compared with nRF52832-QFAA and CC2640R2F, BLUENRGCSP provides strict separation between host application logic and BLE protocol handling via ACI-reducing host MCU firmware complexity, simplifying certification, and enabling independent BLE stack updates without host reflash.

Availability

BLUENRGCSP is available at Aetrix Electronics and suitable for fitness trackers, smart watches, consumer medical sensors, and home automation nodes requiring stable component supply, long-lifecycle support, and verified WLCSP34 packaging for high-volume wearable production.

Supply support for BLUENRGCSP 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, delivering microcontrollers, analog ICs, MEMS, and power solutions across automotive, industrial, and consumer markets.

BLUENRGCSP belongs to ST's BlueNRG family of ultra-low-power BLE network processors-designed specifically to offload BLE protocol handling from host MCUs in space- and energy-constrained devices such as wearables and medical sensors.

FAQ

What is the function of the SMPSFILT1 and SMPSFILT2 pins on BLUENRGCSP?

SMPSFILT1 is the DC-DC converter output filter pin, connecting to an external LC filter to stabilize the 1.2 V SMPS rail. SMPSFILT2 serves as the SMPS feedback/input node-used to configure output voltage and regulate loop stability. Both pins must be populated per ST's reference design (Figure 7) when enabling the DC-DC converter; leaving them unconnected defaults to LDO-only operation.

Does BLUENRGCSP require external flash memory for BLE stack storage?

No. The BLE stack is pre-programmed into the device's internal 64 KB Flash memory and can be upgraded in-field via SPI without external memory. This eliminates BOM cost and PCB area for external storage, and ensures deterministic boot behavior since all stack code resides on-die with ECC protection.

Can BLUENRGCSP operate without a 32 kHz crystal?

Yes. The device supports either a 32.768 kHz crystal (for ±50 ppm accuracy in connection intervals) or its internal 32 kHz ring oscillator (±500 ppm). Using the ring oscillator reduces BOM count and board area but may increase advertising packet drift-acceptable for non-time-critical beacon use cases.

How does the SPI_IRQ pin behave during low-power modes?

SPI_IRQ remains functional in all low-power modes except deep-sleep with ACI disabled. It asserts low to signal pending ACI data (e.g., connection event, GATT notification), and is designed as open-drain with internal weak pull-up-requiring an external 10 kΩ pull-down resistor to ensure clean logic-low assertion and prevent floating states during host wake-up sequencing.