Product Info

Wi-Fi&BT Module Series
FC21 Hardware Design
FC21_Hardware_Design 19 / 52
3.4. Power Supply
3.4.1. Pin Introduction
The following table shows the power supply pins and the ground pins of FC21. The VIO power supply is
recommended to be powered by VDD_EXT of EC2x&EG2x-G modules.
Table 5: Power Supply Pins and GND Pins
FC21 is powered by VDD_3V3, and it is recommended to use a power supply chip with maximum output
current more than 0.6A.
The following figure shows a reference design for VDD_3V3. Pulling PM_ENABLE to a high voltage level
will enable VDD_3V3 power output. And this pin should be connected to pin 127 of EC2x&EG2x-G. For
more details, please refer to document [2], [3], [4], [5] or [6].
TPS630242
L1
L1
L2
L2
VIN
VIN
VIN
VINA
GND
EN
VOUT
VOUT
VOUT
PFM/PWM
FB
PGND
D2
D3
E1
E2
E3
E4
C4
D1
B1
A1
L1 L2
PGND
PGND
U402
D4
B2
B3
A2
A3
A4
B4
C1
C2
C3
C406
R408
C405
10 µF
1M
L401
1 µH
R407
100K
22 µF
C407
22 µF
PM_ENABLE
DC_5V
DC_5V
VDD_3V3
Figure 3: Reference Circuit for VDD_3V3
Pin Name Pin No. Description Min. Typ. Max. Unit
VDD_3V3 21
Main power supply for the
module
3.14 3.3 3.46 V
VIO 11
Power supply for the module’s
I/O pins
1.71 1.8 3.46 V
GND
1, 12, 20, 28,
29, 31, 36,
38~40,
43~45,
48~52
Ground
批注 [RL7]: 中文下面有个单独
的 3.4.1 引脚介绍，是否要加上