5.2 Board Controller Power
The Board Controller is responsible for important features such as the debugger and is powered exclusively through the USB port loca-
ted in the middle left side of the WSTK Mainboard. This part of the kit resides on a separate power domain, so a different power source
can be selected for the target device while retaining debugging functionality. This power domain is also isolated to prevent current leak-
age from the target power domain when power from the Board Controller is removed.
The Board Controller power domain is exclusively supplied by the J-Link USB port, and is not influenced by the position of the power
switch.
The kit has been carefully designed to keep the Board Controller and the target power domains isolated from each other as one of them
powers down. This ensures that the target WGM110 device will continue to operate in the
USB
and
BAT
modes.
5.3 Wi-Fi Module Reset
The WGM110 Wi-Fi Module can be reset by the following methods:
• A user pressing the RESET button.
• The on-board debugger pulling the
#RESET
pin low.
• An external debugger pulling the
#RESET
pin low.
In addition to the reset sources mentioned above, the Board Controller will also issue a RESET to the WGM110 Module when booting
up. This means that removing power to the Board Controller (plugging out the J-Link USB cable) will not generate a RESET, but plug-
ging the cable back in will, as the Board Controller boots up.
5.4 Battery Holder
In radio applications with high output power, peak current consumption will exceed the current sourcing capacity of a coin-cell battery.
To support evaluation of the Wizard Gecko WGM110 Module in situations where powering the kit from a wired USB connection is im-
practical, for instance during range-tests, the WSTK is supplied with an external battery holder for 2 AA batteries.
To use the battery holder, first set the power switch to the
BAT
position. Then attach the cable to
Pin 1
and
Pin 2
on the expansion
header, orienting the connector so that the black wire is connected to the bottom pin (
Pin 1
) and the red wire to the top pin (
Pin 2
).
Connect battery holder
to EXP header.
- Pin 2 (up): Red wire
- Pin 1 (down): Black wire
Put power switch in BAT position
Figure 5.2 Battery Holder Connection to the WSTK Mainboard
Warning:
There is no reverse voltage protection on the VMCU pin! Ensure that the battery holder is connected the right way.
Failure to do so may result in damage to the radio board and its components.
UG172: Wizard Gecko Wi-Fi® Module Wireless Starter Kit SLWSTK6120A User's Guide
Power Supply and Reset
silabs.com
| Smart. Connected. Energy-friendly.
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