Uart; Adc; Strapping Pins - Espressif ESP32­-S3 Series Hardware Design Manuallines

2 Schematic Checklist
VDD33
2.5 RF
C
A π-type matching network is essential for antenna matching in the circuit design. CLC structure is
C6
recommended for the matching network. It is also recommended to add an LC filter circuit at the π-type
10uF
matching network side to suppress secondary harmonics. The parameters of the components in the matching
network are subject to the actual antenna and PCB layout. Figure
GND
ANT1
PCB_ANT
B
The values of C11, L2 and C12
vary with the actual PCB board.
NC: No component.

2.6 UART

You need to connect a 499 Ω series resistor to the U0TXD line in order to suppress the 80 MHz harmonics.

2.7 ADC

A
It is recommended to add a 0.1 µF filter capacitor to a pad when using the ADC function. ADC1 is
recommended for use.

2.8 Strapping Pins

Note:
The content below is excerpted from Section Strapping Pins in
ESP32-S3 has four strapping pins:
• GPIO0
• GPIO45
• GPIO46
• GPIO3
Software can read the values of corresponding bits from register "GPIO_STRAPPING".
Espressif Systems
C3
1uF
GND
L1
C7 C8
1uF 0.1uF
GND GND
RF_ANT
1 L2
2
L3 C11
TBD TBD
GND GND
C5
TBD
GND
Figure 9: Schematic for RF Matching
5
Submit Documentation Feedback
C2
10nF
GND
0
C9
TBD
9 shows the RF matching schematic.
GND
LNA_IN
TBD
C12
CHIP_PU
TBD GPIO0
GPIO1
GPIO2
GND GPIO3
GPIO4
GPIO5
GPIO6
GPIO7
GPIO8
GPIO9
VDD33
ESP32-S3 Series Datasheet.
13
ESP32-S3 Series Hardware Design Guidelines v1.0
GND
1
LNA_IN
2
VDD3P3
3
VDD3P3
4
CHIP_PU
5
GPIO0
6
GPIO1
7
GPIO2
8
GPIO3
9
GPIO4
10
GPIO5
11
GPIO6
12
GPIO7
13
GPIO8
14
GPIO9
U1
C15
0.1uF
GND
4