ESP32-S2 mini by Wemos Pinout

ESP32-S2 mini pinout from wemos. Includes Device Firmware Upgrade Mode and LED pins. Plus exhaustive pin list from Espresif Chip.

It was difficult to find the ESP32 S2 Mini pinout and even the wemos website does not specify what the pins are save for in the datasheet. According to the images The ESP32 S2 mini pinouts show pins 1-18,21,33-40 being accessible via the board.

Link to the datasheet: https://www.wemos.cc/en/latest/s2/s2_mini.html

Features of the board:

  • USB Type-C
  • 4MB Flash
  • 2MB PSRAM
  • 20 ADCs 18 available through pins (These are run off of two ADC ICs at Signified by ADC1 and ADC2{Chips naming convention not ours [we count with 0 being the first]})
    • ESP32-S2 integrates two 13-bit SAR ADCs thus the ADC1 and ADC2
  • 2 DACS
  • SPI, UART, and USB On The Go

Full Resolution ESP32-S2 Mini Pinout 2560×1670: https://openmuscle.org/wp-content/uploads/2022/12/ESP32_S2_mini_V2-R6-Open-Muscle-01-scaled.jpg

The image shows the ESP32-S2 pinout numbers but doesn’t specify any other information: which are ADCs which are I2C… etc.

We are currently using the ESP32 S2 pinout and the ESP32 C3 for our testing upcoming devices and will be publishing everything we find here on the site. Above you will find the ESP32 S2 diagram that we created for our use. We are also updating it as we continue to test the boards that we ordered a batch of.


The ESP32-S2 is a very promising chip that has all of the features we are looking for for the Open Muscle Prototype Version 3.

It is interesting that you can use any of the pins for SDA and SCL IIC comunicatons or I2C.
This post here had the same query: https://www.esp32.com/viewtopic.php?t=16416

More Chip information: https://www.espressif.com/en/products/socs/esp32-s2

Pin Description Table:

Pin#No.TypeNameFunction and Description of pins/pinouts

1PaVDDAAnalog Power Supply

2I/OLNA_INRF input and output

3PaVDD3P3Analog Power Supply

4PaVDD3P3Analog power supply
05I/O/T
GPIO0
16I/O/T
GPIO1, Touch1, ADC1_CH0
27I/O/T
GPIO2, Touch2, ADC1_CH1
38I/O/T
GPIO3, Touch3, ADC1_CH2
49I/O/T
GPIO4, Touch4, ADC1_CH3
510I/O/T
GPIO5, Touch5, ADC1_CH4
611I/O/T
GPIO6, Touch6, ADC1_CH5
712I/O/T
GPIO7, Touch7, ADC1_CH6
813I/O/T
GPIO8, Touch8, ADC1_CH7
914I/O/T
GPIO9, Touch9, ADC1_CH8, FSPIHD
1015I/O/T
GPIO10, Touch10, ADC1_CH9, FSPICS0, FSPIIO4
1116I/O/T
GPIO11, Touch11, ADC2_CH0, FSPID, FSPIIO5
1217I/O/T
GPIO12, Touch12, ADC2_CH1, FSPICLK, FSPIIO6
1318I/O/T
GPIO13, Touch13, ADC2_CH2, FSPIQ, FSPIIO7
1419I/O/T
GPIO14, Touch14, ADC2_CH3, FSPIWP, FSPIDQS

20PaVDD3P3_RTCAnalog Power Supply
1521
XTAL_32K_PGPIO15, U0RTS, ADC2_CH4, XTAL_32K_P
1622
XTAL_32K_NGPIO16, U0CTS, ADC2_CH5, XTAL_32K_N
1723
DAC_1GPIO17, U1TXD, ADC2_CH6, DAC_1
1824
DAC_2GPIO18, U1RXD, ADC2_CH7, DAC_2, CLK_OUT3
1925

GPIO19, U1RTS, ADC2_CH8, CLK_OUT2, USB_D-
2026

GPIO20, U1CTS, ADC2_CH9, CLK_OUT1, USB_D+

27PdVDDP3P_RTC_IOInput power supply for RTC IO
2128I/O/T
GPIO21
2629I/O/T
GPIO26, SPICS1 (Used for embedded PSRAM)

30PdVDD_SPIOutput power supply: 1.8 V or the same voltage as VDD3P3_RTC_IO
2731I/O/TSPIHDGPIO27, SPIHD (Used for embedded flash)
2832I/O/TSPIWPGPIO28, SPIWP (Used for embedded flash)
2933I/O/TSPICS0GPIO29, SPICS0 (Used for embedded flash)
3034I/O/TSPICLKGPIO30, SPICLK (Used for embedded flash)
3135I/O/TSPIQGPIO31, SPIQ (Used for embedded flash)
3236I/O/TSPIDGPIO32, SPID (Used for embedded flash)
3337I/O/T
GPIO33, SPIIO4, FSPIHD
3438I/O/T
GPIO34, SPIIO5, FSPICSO
3539I/O/T
GPIO35, SPIIO6, FSPID
3640Pd
GPIO36, SPIIO7, FSPICLK
3741I/O/T
GPIO37, SPIDQS, FSPIQ
3842I/O/T
GPIO38, FSPIWP
3943I/O/TMTCKGPIO39, MTCK, CLK_OUT3
4044I/O/TMTDOGPIO40, MTDO, CLK_OUT2

45PdVDD3P3_CPUInput Power Supply for CPU IO
4146I/O/TMTDIGPIO41, MTDI, CLK_OUT1
4247I/O/TMTMSGPIO42, MTMS
4348I/O/TU0TXDGPIO43, U0TXD, CLK_OUT1
4449I/O/TU0RXDGPIO44, U0RXD, CLK_OUT2
4550I/O/T
GPIO45

51PaVDDAAnalog Power Supply

52XTAL_NExternal crystal output

53XTAL_PExternal crystal output

54PaVDDAAnalog power supply
4655I
GPIO46

56ICHIP_PUHigh: on, enables the chip Low: off, the chip powers off
ESP32-S2 Pinout gleaned from the data in this document: https://www.espressif.com/sites/default/files/documentation/esp32-s2_datasheet_en.pdf

The pin values in bold can be found on the esp32-s2 mini v1.0.0 board the ones with a strikethrough where not routed to header pins. There will be more information posted as more testing is conducted.