3
PCB Layout Design
Figure 20: ESP32C3 Family PCB Stackup Design
3.6 Flash
Place the reserved serial resistor on the SPI interface close to the chip side. Route the SPI traces on the inner
layer (e.g., the third layer) whenever possible. Add ground copper and ground vias around the clock and data
traces of SPI separately.
Figure 21: ESP32C3 Family Flash Layout
3.7 UART
The series resistor on the U0TXD line needs to be placed close to the chip and away from the crystal. The
U0TXD and U0RXD traces on the top layer should be as short as possible, surrounded by ground copper and
ground vias.
Espressif Systems
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ESP32-C3 Family Hardware Design Guidelines V1.0