NINA-B3 series - System integration manual 
UBX-17056748 - R13  System description  Page 9 of 72 
C1-Public 
1.3  Pin configuration and function 
See the NINA-B3 series data sheet [2] for information about pin configuration and function. 
1.4  Supply interfaces 
1.4.1  Main supply input 
The NINA-B3 series uses an integrated DC/DC converter to transform the supply voltage presented 
at  the  VCC  pin  into  a  stable  system  core  voltage.  Because  of  this,  the  NINA-B3  modules  are 
compatible for use in battery powered designs.  
When using the NINA-B3 with a battery, it is important that the battery type can handle the peak 
power of the module. For the battery supply, consider adding extra capacitance on the supply line to 
avoid  capacity  degradation.  See  the  NINA-B3  series  data  sheet  [2]  for  information  about  voltage 
supply requirements and current consumption. 
Table 2: Summary of voltage supply requirements 
☞  The  current  requirement  in  Table  2  considers  using  the  u-connectXpress  software  with  UART 
communications.  But  it  does  not  include  any  additional  I/O  current.  Any  use  of  external  push 
buttons,  LEDs,  or  other  interfaces  will  add  to  the  total  current  consumption  of  the  NINA-B3 
module. The  peak current consumption of the entire design will need to be taken into account 
when considering a battery powered solution. 
1.4.2  Digital I/O interfaces reference voltage (VCC_IO) 
On NINA-B3 series modules, the I/O voltage level is the same as the supply voltage and  VCC_IO is 
internally connected to the supply input VCC.  
When using NINA-B3 with a battery, the I/O voltage level will vary with the battery output voltage, 
depending on the charge of the battery. Level shifters might be needed depending on the I/O voltage 
of the host system.  
1.4.3  VCC application circuits 
The power for  NINA-B3 series modules is provided through the VCC pins, which  can be one of the 
following: 
•  Switching Mode Power Supply (SMPS) 
•  Low Drop Out (LDO) regulator 
•  Battery 
The SMPS is the ideal choice when the available primary supply source has a higher value than the 
operating supply voltage of the NINA-B3 series modules. The use of SMPS provides the best power 
efficiency for the overall application and minimizes the current drawn from the main supply source. 
⚠  While selecting SMPS, ensure that the AC voltage ripple at the switching frequency is kept as low 
as possible. Layout shall be implemented to minimize impact of high frequency ringing.  
The use of an LDO linear regulator  is convenient for a primary supply with a relatively low voltage 
where the typical 85-90% efficiency of the switching regulator leads to minimal current saving. Linear 
regulators  are  not  recommended  for  high  voltage  step-down,  as  these  dissipate  a  considerable 
amount of energy.