u-blox NINA-B112 System Integration Manual

Also see for NINA-B111: Manual Getting started

u-blox NINA-B112 System Integration Manual Manual pdf 33 page image

NINA-B1 series - System Integration ManualUBX-15026175 - R09 Design-inPage 33 of 49It is recommended to place the NINA-B112 module so that the internal antenna is in the corner of the host PCB(Pin 15/16 should be in the corner) as shown in Figure 12. The antenna side (short side closest to the antenna),positioned along one side of the host PCB ground plane is the second best option. It is beneficial to have a largeground plane on the host PCB and have a good grounding on the NINA-B1 module.Figure 12: NINA-B112 with internal antennaTake care when handling the EVK-NINA-B112. Applying force to the NINA-B112 module mightdamage the internal antenna.3.3 Supply interfaces3.3.1 Module supply designGood connection of the module’s VCC pin with DC supply source is required for correct RF performance. Theguidelines are summarized below:• The VCC connection must be as wide and short as possible.• The VCC connection must be routed through a PCB area separated from sensitive analog signals andsensitive functional units. It is a good practice to interpose at least one layer of PCB ground betweenVCC track and other signal routing.There is no strict requirement of adding bypass capacitance to the supply net close to the module. Butdepending on the layout of the supply net and other consumers on the same net, bypass capacitors might stillbe beneficial. Though the GND pins are internally connected, connect all the available pins to solid ground onthe application board, as a good (low impedance) connection to an external ground can minimize power lossand improve RF and thermal performance.3.4 Data communication interfaces3.4.1 Asynchronous serial interface (UART) designThe layout of the UART bus should be done so that noise injection and cross talk are avoided.It is recommended to use the hardware flow control with RTS/CTS to prevent temporary UART buffer overrun.• If CTS is 1, then the Host/Host Controller is allowed to send.• If CTS is 0, then the Host/Host Controller is not allowed to send.