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Rev. 1.20
9
October 28, 2020
BC45B4523
BC45B4523
TX1
TX2
RX
VMID
XTAL1
XTAL2
27.12MHz
VREG_IN
T_VDD
100nF
100nF
10µF
A_VDD
VREG
_OUT
IO_VDD
MCU
(3.3V)
VDD
T_VSS
D_VSS
A_VSS
D_VDD
100nF
+1.
6 V
+3.3 V Power
RSTPD
IRQ
NCS
SCK
MOSI
MISO
TA
TD
Be
ad
100nF
10µF
Be
a
d
+5.0 V from USB Power
Typical Operating Circuit for External Power Supply (Not Apply On-Chip 3.3V Regulator)
BC45B4523
TX1
TX2
RX
VMID
XTAL1
XTAL2
27.12MHz
VREG
_IN
T_
VD
D
100nF
100nF
10µF
A_
VD
D
100nF
10µF
VREG_OUT
100nF
10µF
IO
_V
D
D
MCU
(3.3V)
VDD
T_VSS
D_VSS
A_VSS
D_
VD
D
100nF
+1.6 V
+3.
3 V
+3.3 V
+5.0 V from USB Power
RSTPD
IRQ
NCS
SCK
MOSI
MISO
TA
TD
Be
ad
Typical Configuration Employing On-Chip Regulator for MCU with 3.3V I/O