Data Sheet

NINA-B40 series - Data sheet
UBX-19049405 - R04 Interfaces Page 10 of 40
C1 - Public
2.2.3 Direction Finding (AoA/AoD)
NINA-B40 modules support a location Bluetooth 5.1 service called Bluetooth Direction Finding. This
service is used for indoor positioning, wayfinding, and tracking assets.
These phase-based functions require an antenna array, estimation algorithms and processing power
to make it possible to triangulate and detect the direction of a Bluetooth signal down to a sub-meter
accuracy. These functions are available for 1 Mbps and 2 Mbps Bluetooth LE modes.
The Angle of Arrival (AoA) receiver and Angel of Departure (AoD) transmitter use the antenna arrays
that are switched on one by one. This switching sequence allows the direction of a peer device to be
calculated. The derived IQ samples are used to determine the relative path lengths between the
antenna pairs and subsequent location of the transmitter.
2.3 System functions
2.3.1 Power modes
NINA-B40 series modules use power-efficient LDO and DC/DC regulators and can operate in different
power modes and configurations. Consequently, specific parts of the module can be powered off when
they are not needed and complex wake-up events can be generated from different external and
internal inputs.
2.3.1.1 System OFF mode
System OFF mode is the deepest power saving mode. It is in this mode that NINA-B40 modules sleep,
so that all functionality is stopped to ensure minimum power consumption.
An external event is required to wake up the module from sleep in the system OFF mode. Although
the module always reboots after waking up from the system OFF mode, some non-volatile registers
in RAM can be configured so that they remain intact during and after going to the system OFF mode.
You can switch on or reboot NINA-B40 modules in any of the following ways:
 Rising edge of the VCC pin connected to a valid supply voltage
 Module reset, as described in section 2.3.2.
 Programmable digital or analog sensor event. In response to a rising voltage level flag from an
analog comparator pin, or similar.
 NFC field detection
 5 V supply to the VBUS pin (USB interface plug in)
2.3.1.2 System ON mode
When powered on or reset, NINA-B40 modules return to the default configuration set by the
application software flashed in the module. In System ON mode all functional blocks and system
peripherals are available in either RUN mode or in IDLE mode. The software configuration and the
application under execution determines the mode of operation.
System ON mode has two optional sub-power modes, Constant Latency and Low-Power, as described
in sections 0 and 2.3.1.2.2 respectively. Designers can choose which sub-power mode is most
appropriate for the application, but only one can be enabled at any given time. These modes are active
when the CPU or other peripherals are idling.