SiM3U1xx
Preliminary Rev. 0.8
7
Figure 2.3. Connection Diagram with Voltage Regulator Used and USB Connected (Bus-Powered)
Figure 2.4 shows a typical connection diagram for the power pins of the SiM3U1xx devices when the internal
regulator used and USB is connected (self-powered). The VBUS signal is used to detect when USB is connected
to a host device.
Figure 2.4. Connection Diagram with Voltage Regulator Used and USB Connected (Self-Powered)
Figure 2.5 shows a typical connection diagram for the power pins of the SiM3U1xx devices when the internal
regulator used, USB is connected (bus-powered), and the VIO and VIOHD pins are sourced from separate
supplies.
SiM3U1xx Device
VREGn
VREGIN
VSS
VSSHD
1 uF and 0.1 uF bypass
capacitors required for
each power pin placed
as close to the pins as
possible.
3.3 V (out)
VBUS
USB 5 V (in)
VDD
VIO
VIOHD
SiM3U1xx Device
VREGn
VREGIN
VSS
VSSHD
1 uF and 0.1 uF bypass
capacitors required for
each power pin placed
as close to the pins as
possible.
3.3 V (out)
VBUS
USB 5 V
(sense)
VDD
VIO
VIOHD
3.6-5.5 V (in)