3.1 Power Supply

The WBZ450 Curiosity Board can be powered using any of the following sources:

  1. The USB supplies power to the WBZ450 Curiosity Board using a Type-A male to Micro-B USB cable connected to the Micro-B USB connector (PS) (J7).
  2. 4.2V Li-ion/Li-Po battery kit as follows:
    • Connected to J5, JST PH, 2-pin, 2 mm pitch and right-angle male battery header
    • Crimp style connector, battery polarity according to ± marking on the Curiosity Board
    • Battery is not part of the kit
    • Minimum recommended battery capacity is 400 mAh with a battery charge voltage of 4.2V

Battery management circuit automatically handles selection between USB power supply and battery supply.

The following are the two on-board MCP1727 voltage regulators on the WBZ450 Curiosity Board that power the circuitry on-board.
  • U3 – Generates 3.3V that powers the WBZ450PE Module along with the associated circuits
  • U7 – Generates 3.3V that powers the PKOB4 controller (U11), along with the associated circuits that connect the PKOB4 debugger to a host PC

For more details on the U3 and U7 voltage regulators, refer to the MCP1727 1.5A, Low Voltage, Low Quiescent Current LDO Regulator Data Sheet (DS21999).

Figure 3-2. WBZ450 Curiosity Board Power Supply Block Diagram

The WBZ450PE Module and associated peripherals can also be powered from:

  • External power supply header (J3) using external power supply (1.9-3.6V) for testing at different voltage levels apart from the default supply of 3.3V from on-board regulator. To use the external power supply header, disconnect the on-board 3.3V supply according to the following table:
Table 3-2. Resistor Option to Select the WBZ450PE Module Power Supply

On-board 3.3V Regulator

External Power Supply

Mount R10

Do not mount R10

Do not mount R17

Mount R17

Figure 3-3. Resistor Position to Select the WBZ450 Module Power Supply
Note: The maximum available current from the Micro-B USB Connector (PS) (J7) is limited to 500 mA. The current is shared between charging the external battery (if connected) and the target application section.