BlueNRG-1 bluetooth without hassle

Designing and impendance matching RF-related circuitry is an art of its own. STMicroelectronics’s SPBTLE-1S combines a Bluetooth 4.2 radio module with a Cortex-M0 processor intended to handle RF communications.

A look at the block diagram confirms that the module is, by and large, an SoC in a box. Thanks to STM pre-soldering it all onto a planar, certification hassles are avoided (in the USA) or mitigated (in Europe).

The SPBTLE-1S contains all an IoT developer dreams of at night…

Interaction with external hardware can be accomplished via a full complement of GPIO ports, two ADC channels, one SPI and two I2C interfaces. The module, furthermore, has the capability to work as a dedicated Bluetooth 4.2 radio chip being controlled by a seperate microcontroller.

ST Microelectronics prides itself on the module being able to run from a single coin cell or a pair of AAA batteries – any input power ranging from 1-.7V to 3.6V is acceptable. This, sadly, is a problem for hosted mode – interfacing the module with a run of the mill 5V microcontroller requires level switching hardware. Power consumption in active mode is 1.9mA, with a 0.9 Microampere sleep mode also available.

Integrating the module is relatively simple: STMicroelectronics picked a form factor similar to the one used by the various ESP32 modules. This means that even non-sophisticated pick and place houses should not have trouble handling the part – if land geometry is suitable, hand soldering also is possible due to the pads being exposed from both sides.

…the SPBTLE-1S can be soldered by hand

Unlike some other products from STM, the SPBTLE-1S does not stand alone. It, instead, can use almost all example code provided for the BlueNRG platform – getting started with it is as easy as selecting a C program’s skeleton which fits your needs.