1.2.1 Power Supply

The RNBD451 Add On Board can be powered using any of the following sources depending on the use case scenario:

  1. USB supplies power to the RNBD451 Add On Board using a USB Type-C cable connected to the USB Type-C Connector (J7). The module and the peripherals are powered by 3.3V generated from the on-board 3.3V linear regulator.
  2. The RNBD451 module and the peripherals are powered by 3.3V at J3, the mikroBUS interface when plugged into a host board.

Power selection between USB power supply or the 3.3V from the mikroBUS interface is done by mounting a jumper cap JP1 on J2.

Table 1-1. Jumper Cap JP1 Position to Select Power Supply Using J2 Power Supply Selection Header

3.3V generated from USB Power Supply

3.3V from mikroBUS interface

JP1 on J2-3, J2-2

JP1 on J2-1, J2-2

Figure 1-4. RNBD451 Add On Board Power Supply Block Diagram

To measure the current consumed by the RNBD451PE module alone, remove R6 and connect an ammeter across it.