For energy-constrained smart sensors and connected devices, Bluetooth Low Energy devices must ensure energy-efficient operation, including extremely low power consumption in sleep and standby modes that are used frequently to maximize battery life. Strong radio performance is also needed to advertise availability and connect reliably. ST has designed its new BlueNRG-1 programmable SoC with performance and power to satisfy these requirements.
The BlueNRG-1 single-core SoC hosts a 32 MHz ARM Cortex-M0 core with 160 kByte of on-chip Flash memory for application-code and data storage besides the possibility to upgrade the ST Bluetooth Low Energy firmware stack. ST has employed proven ultra-low-power design, including support for fast wake-up and sleep transitions, and sub-1µA standby current.
BlueNRG-1 comes with ST’s Bluetooth Low Energy stack in the form of a ready-to-use linkable library. Library linking at build-time removes unused parts of the stack so as to ensure efficient memory utilization. Pre-certified profiles for medical devices, proximity monitor and other devices are provided, as well as tools and collaterals that support app development for iOS or Android devices.
Peripherals that help simplify design and reduce component count include a 10-bit ADC, SPI and I²C master/slave units, UART, and up to 15 user-configurable I/Os depending on package type.
BlueNRG-1 can be connected directly to ST’s single-chip balun for converting between the balanced transceiver signal and the single-ended antenna signal. Available as a QFN device, the balun integrates a network of nine passive components on a single die using ST’s IPD-on-glass technology.
Designers using BlueNRG-1 have access to a comprehensive development ecosystem, including a software development kit (SDK) with APIs, sensor drivers, and sample applications. Recognizing the importance of power consumption in Bluetooth Low Energy applications, there is also a current-estimation tool that helps assess the effects of changing factors such as transmit output power, master/slave sleep clock accuracy, RAM retention, connection advertising or scanning interval, data length, and DC-DC converter activation.