esp32s2 Development Boards

The list of esp32s2 development boards, complete with pinouts, technical specifications, datasheets and more.

The ESP32-S2 is a single-core Wi-Fi SoC designed for secure IoT applications. It adds advanced hardware security features like cryptographic acceleration, secure boot, and flash encryption, making it ideal for connected appliances, smart locks, and enterprise IoT.

While it does not support Bluetooth, it includes native USB OTG, making it great for USB devices or web USB interfaces. Developers use the ESP-IDF or Arduino Core with full support.

Technical Specifications

🧠 Microcontroller

Microcontroller Xtensa single-core 32-bit LX7

Frequency Up to 240 MHz

📡 Connectivity

WiFi 802.11 b/g/n 2.4 GHz

Bluetooth -

BLE -

🔌 Interfaces

Analog-Digital Converter (ADC) Two 13-bit, 20 Channels

Digital-Analog Converter (DAC) Two 8-bit Channels

SPI 4

I2C 1

I2S 1

RMT 4 Channels

Touch Sensor Pins 14

📄 View Datasheet

Strapping Pins

Some pins are reserved for critical functions like bootstrapping, JTAG debugging, USB communication, and flash memory operations. Misusing these pins may lead to boot failures, programming issues, USB conflicts, or disruptions in flash storage.

Critical Pin Categories:

🛠️ Strapping Pins: Control boot behavior and flash voltage selection
🔗 JTAG Debugging Pins: Required for low-level debugging
🔌 USB Communication Pins: Used for USB Serial/JTAG communication
⚡ Flash Memory & SPI Pins: Connected to SPI flash memory and PSRAM
📡 UART Serial Communication Pins: Used for debugging and firmware uploads

PIN	Label	Reason	Function
IO0	GPIO0	Must be pulled high for normal boot; pulling low at reset enters bootloader (download mode). Also serves as SPI flash data-in (SPID) line when using external flash memory.	🛠️ Strapping
IO9	FSPIHD	Typically used as flash/PSRAM IO line in certain configurations; avoid using as GPIO if flash or PSRAM is present.	⚡ Flash
IO10	FSPICS0	Often used as flash chip select in some designs; not available for GPIO when controlling flash.	⚡ Flash
IO11	FSPID	Used for flash data transfer in certain configurations; should be avoided for general use if flash is connected.	⚡ Flash
IO12	FSPICLK	Used as flash clock line in some boards; not free for GPIO if driving flash.	⚡ Flash
IO13	FSPIQ	Used for flash data output in certain configurations; avoid using as GPIO if connected to flash.	⚡ Flash
IO14	FSPIWP	Used as flash write-protect/data line on some modules; not recommended for other usage.	⚡ Flash
IO15	XTAL_32K_P	If an external 32 kHz crystal is used for RTC, this pin is dedicated to the crystal and cannot be used as GPIO.	🪛 Other
IO16	XTAL_32K_N	If using an external 32 kHz crystal, this pin is connected to the crystal and should not be used as general I/O.	🪛 Other
IO19	USB_D-	Used for USB communication; using this pin as general GPIO can interfere with USB functionality.	🔌 USB
IO20	USB_D+	Dedicated to USB interface; repurposing as GPIO may disrupt USB connectivity.	🔌 USB
IO26	SPICS1	Used to connect external PSRAM (or second SPI memory); should be avoided as GPIO if such memory is present.	⚡ Flash
IO29	SPICS0	Connected to external or embedded flash memory chip; not recommended for use as GPIO.	⚡ Flash
IO30	SPICLK	Drives external or internal SPI flash clock; tied to flash operation, so not free for GPIO use.	⚡ Flash
IO31	SPIQ	Used for SPI flash data; reserved for flash communications (embedded or external).	⚡ Flash
IO32	SPID	Used for SPI flash data; reserved for flash communications (embedded or external).	⚡ Flash
IO33	SPIHD	Connected to SPI flash (hold/data line); not available for general-purpose use.	⚡ Flash
IO34	SPIWP	Connected to SPI flash (write-protect/data line); not recommended for other use.	⚡ Flash
IO35	FSPID	Used by internal flash/PSRAM on some ESP32-S2 variants; avoid using as GPIO to prevent conflicts.	⚡ Flash
IO36	FSPICLK	May be connected to internal flash or used for high-speed SPI; not intended for general GPIO use.	⚡ Flash
IO37	FSPIQ	Used for internal flash/PSRAM data in some models; should not be repurposed for GPIO.	⚡ Flash
IO38	FSPIWP	Reserved for flash/PSRAM in ESP32-S2 modules with internal memory; not recommended for general I/O.	⚡ Flash
IO39	MTCK	Used for JTAG debugging interface; using this pin for other purposes will disable JTAG clock input.	🪛 Other
IO40	MTDO	Part of JTAG interface (TDO); should be avoided as GPIO if JTAG debugging is needed.	🪛 Other
IO41	MTDI	Part of JTAG interface (TDI); avoid using as GPIO to retain ability for JTAG debug.	🪛 Other
IO42	MTMS	JTAG TMS pin; should not be repurposed if JTAG debugging or programming via JTAG is required.	🪛 Other
IO45	GPIO45	Must be set correctly at boot (usually low for 3.3 V); improper level can cause boot failure or flash malfunction.	🛠️ Strapping
IO46	GPIO46	If pulled high during boot, it can disable bootloader log output (depending on eFuse settings). Cannot drive output (input-only pin).	🛠️ Strapping