EFM32WG Datasheet, PDF (243/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

Figure 15.5. OTG Dual Role Device (5V)
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VDD
EFM3 2
USB_VREGO
USB_VREGI
GPIO (over-current )
USB_VBUSEN
USB_VBUS
USB_DP
USB_DM
USB_ID
5V
Power swit ch +
over-current detection
OC ^Vin
EN _Vout
VBUS
D+
D-
ID
GND
15.3.2.5 OTG Dual Role Device (5V step-up regulator)
An OTG Dual Role Device (5V step-up regulator) configuration is shown in Figure 15.6 (p. 243) . When
5V is not available, an external 5V step-up regulator is needed. In this configuration, the voltage for the
EFM32 must be in the range 3.0V - 3.6V. In this mode the voltage regulator is bypassed by connecting
both the input and output to the external supply. This effectively causes the PHY to be powered directly
from the external 3.0 - 3.6 V supply. The voltage regulator should be disabled when operating in
this mode. For over-current detection a regular GPIO input pin with interrupt is used. The application
should turn off or limit VBUS power when over-current is detected. In OTG mode, the maximum VBUS
decoupling capacitance is 6.5 uF.
In this configuration, the VREGO sense circuit should be left disabled.
Figure 15.6. OTG Dual Role Device (5V step-up regulator)
3.0V – 3.6V
VDD
USB_VREGI
USB_VREGO
EFM3 2
GPIO (over-current )
USB_VBUSEN
5V step-up
OC ^Vin
EN _Vout
USB_VBUS
USB_DP
USB_DM
USB_ID
VBUS
D+
D-
ID
GND
15.3.2.6 Host
A host configuration is shown in Figure 15.7 (p. 244) . In this example a 5V step-up regulator is used.
If 5V is available, a power switch can be used instead, as shown in Figure 15.5 (p. 243) . The host
configuration is equal to OTG Dual Role Device, except for the USB_ID pin which is not used and the
USB connector which is a USB Standard-A Connector. In host mode, the minimum VBUS decoupling
capacitance is 96 uF.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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