Silicon Laboratories UG524, User Manual

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3.2 Power Supply
The kit can be powered through one of these interfaces:
• USB Micro-B
• Battery (CR2032 battery or external battery connected through 2-pin battery header)
• Mini Simplicity connector
The figure below shows the power options available on the kit and illustrates the main system power architecture.
USB Micro-B
LDO
5V0
IN OUT
Automatic
Switchover
3V3
VMCU
Battery
EFR32MG24
Wireless SoC
Peripherals
Per
ipher
als
Per
ipher
als
Peripherals
Mini Simplicity
Connector
Figure 3.2. xG24 Dev Kit Power Architecture
Power is normally applied either through the USB cable or a CR2032 battery. A 2-pin 1.25 mm pitch battery connector for external bat-
teries is also available as an alternative to a CR2032 battery. When the USB cable is connected, VBUS is regulated down to 3.3 V. An
automatic switchover circuit switches the main system power from battery power to USB power when the USB cable is inserted, and
protects the battery from reverse current.
Power can also be applied through the Mini Simplicity connector. There must be no other power sources present on the kit as power is
injected directly to the VMCU net. It is important to follow this recommendation to avoid power conflicts and backfeeding the battery.
Powering the xG24 Dev Kit through the Mini Simplicity connector allows current measurements using the Advanced Energy Monitoring
(AEM) as described in section
4.2 External Debugger .
Important: When powering the board through the Mini Simplicity connector, the USB and battery power sources must be removed.
The power supply options are summarized in the table below.
Table 3.1. xG24 Dev Kit Power Options
Supply Mode Typical Input Voltage VMCU Source 3V3 5V
USB power 5.0 V On-board regulator On-board regulator USB VBUS
Battery 3.0 V Battery voltage Disconnected No voltage present
Mini Simplicity 3.3 V Debugger dependent Disconnected No voltage present
3.3 EFR32MG24 Reset
The EFR32MG24 can be reset by a few different sources:
• A user pressing the RESET button.
• The on-board debugger pulling the #RESET pin low.
• An external debugger pulling the #RESET pin low.
UG524: xG24 Dev Kit User's Guide
Hardware
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