ESP32-S2-MINI-2

module
Espressif Systems Datasheet ↗

Integrating ESP32-S2FH4 (4 MB flash) or ESP32-S2FN4R2 (4 MB flash + 2 MB PSRAM) in a 15.4×20.5 mm (PCB antenna) or 15.4×15.4 mm (MINI-2U U.FL) 0.85 mm LGA package, ESP32-S2-MINI-2 exposes up to 37 GPIOs (36 on -N4R2 where Pin 26 IO26 is occupied by internal PSRAM). Pin-for-pin compatible with ESP32-S2-MINI-1.

Silicon IC: ESP32-S2 Boards / Modules: ESP32-S2-SOLO-2 Also known as: ESP32-S2-MINI-2U ESP32-S2-MINI-2-N4 ESP32-S2-MINI-2-N4R2 ESP32-S2-MINI-1
ESPRESSIF S2-MINI-2U 1 GND GND GND 2 GND GND GND 3 3V3 ! 3V3 3V3 4 IO0 ! GPIO0 GPIO0 5 IO1 GPIO1 ADC1_CH0 TOUCH1 GPIO1 ADC1_CH0 TOUCH1 6 IO2 GPIO2 ADC1_CH1 TOUCH2 GPIO2 ADC1_CH1 TOUCH2 7 IO3 GPIO3 ADC1_CH2 TOUCH3 GPIO3 ADC1_CH2 TOUCH3 8 IO4 GPIO4 ADC1_CH3 TOUCH4 GPIO4 ADC1_CH3 TOUCH4 9 IO5 GPIO5 ADC1_CH4 TOUCH5 GPIO5 ADC1_CH4 TOUCH5 10 IO6 GPIO6 ADC1_CH5 TOUCH6 GPIO6 ADC1_CH5 TOUCH6 11 IO7 GPIO7 ADC1_CH6 TOUCH7 GPIO7 ADC1_CH6 TOUCH7 12 IO8 GPIO8 ADC1_CH7 TOUCH8 GPIO8 ADC1_CH7 TOUCH8 13 IO9 GPIO9 ADC1_CH8 TOUCH9 GPIO9 ADC1_CH8 TOUCH9 14 IO10 GPIO10 ADC1_CH9 System SPI +2 GPIO10 ADC1_CH9 TOUCH10 FSPICS0 15 IO11 ! GPIO11 FSPID ADC System +2 GPIO11 ADC2_CH0 TOUCH11 FSPID 16 IO12 ! GPIO12 FSPICLK ADC System +2 GPIO12 ADC2_CH1 TOUCH12 FSPICLK 17 IO13 ! GPIO13 FSPIQ ADC System +2 GPIO13 ADC2_CH2 TOUCH13 FSPIQ 18 IO14 ! GPIO14 ADC2_CH3 TOUCH14 GPIO14 ADC2_CH3 TOUCH14 19 IO15 ! GPIO15 ADC2_CH4 XTAL_32K_P GPIO15 ADC2_CH4 XTAL_32K_P 20 IO16 ! GPIO16 ADC2_CH5 XTAL_32K_N GPIO16 ADC2_CH5 XTAL_32K_N 21 IO17 ! GPIO17 DAC_1 ADC UART +2 GPIO17 ADC2_CH6 DAC_1 U1TXD 22 IO18 ! GPIO18 DAC_2 ADC UART +2 GPIO18 ADC2_CH7 DAC_2 U1RXD 23 IO19 ! GPIO19 ADC2_CH8 USB_D- GPIO19 ADC2_CH8 USB_D- 24 IO20 ! GPIO20 ADC2_CH9 USB_D+ GPIO20 ADC2_CH9 USB_D+ 25 IO21 GPIO21 GPIO21 26 IO26 ! GPIO26 SPICS1 GPIO26 SPICS1 27 NC 28 IO33 GPIO33 GPIO33 29 IO34 GPIO34 GPIO34 30 GND GND GND 31 IO35 GPIO35 GPIO35 32 IO36 GPIO36 GPIO36 33 IO37 GPIO37 GPIO37 34 IO38 GPIO38 GPIO38 35 IO39 GPIO39 MTCK GPIO39 MTCK 36 IO40 GPIO40 MTDO GPIO40 MTDO 37 IO41 GPIO41 MTDI GPIO41 MTDI 38 IO42 GPIO42 MTMS GPIO42 MTMS 39 TXD0 GPIO43 U0TXD GPIO43 U0TXD 40 RXD0 GPIO44 U0RXD GPIO44 U0RXD 41 IO45 ! GPIO45 GPIO45 42 GND GND GND 43 GND GND GND 44 IO46 ! GPIO46 GPIO46 45 EN ! CHIP_PU CHIP_PU 46-65 GND GND GND

Onboard Peripherals & Internal Signals

In-Package 4 MB Flash (+ 2 MB PSRAM on -N4R2) QSPI
Chip Pad: GPIO29
Internal SPI0/1 flash on GPIO27–32

Leave Pin 26 floating on -N4R2.

External Coaxial Antenna Receptacle System
Chip Pad: LNA_IN
Top-left 50Ω coaxial antenna connector

Connect an external 50Ω 2.4 GHz antenna before transmitting.

Pin Assignment Planner

Add the peripherals you need and plan the pin assignments

Full Pin Reference (46 Pins)

Pin # Label Type Functions Warnings & Notes
1 GND ground GND
Module system ground (0V)
2 GND ground GND
Module system ground (0V)
3 3V3 power 3V3
[CAUTION] 3.0V–3.6V supply only (>=500 mA current capability + 10 µF & 0.1 µF decoupling)
Wi-Fi TX bursts draw high peak current. Exceeding 3.6V permanently damages the SoC and onboard flash.
Main 3.3V module power supply input (3.0V–3.6V; >=500 mA regulator recommended)
4 IO0 GPIO0 digital GPIO0
[CAUTION] Boot mode strapping pin (weak pull-up: HIGH=SPI Boot, LOW=Download Boot)
Pulling GPIO0 LOW with GPIO46 LOW at reset enters USB OTG DFU / UART0 Download Boot.
General-purpose 3.3V GPIO0 (NOT 5V tolerant)
5 IO1 GPIO1 mixed GPIO1 ADC1_CH0 TOUCH1
General-purpose 3.3V GPIO1 (NOT 5V tolerant)
6 IO2 GPIO2 mixed GPIO2 ADC1_CH1 TOUCH2
General-purpose 3.3V GPIO2 (NOT 5V tolerant)
7 IO3 GPIO3 mixed GPIO3 ADC1_CH2 TOUCH3
General-purpose 3.3V GPIO3 (NOT 5V tolerant)
8 IO4 GPIO4 mixed GPIO4 ADC1_CH3 TOUCH4
General-purpose 3.3V GPIO4 (NOT 5V tolerant)
9 IO5 GPIO5 mixed GPIO5 ADC1_CH4 TOUCH5
General-purpose 3.3V GPIO5 (NOT 5V tolerant)
10 IO6 GPIO6 mixed GPIO6 ADC1_CH5 TOUCH6
General-purpose 3.3V GPIO6 (NOT 5V tolerant)
11 IO7 GPIO7 mixed GPIO7 ADC1_CH6 TOUCH7
General-purpose 3.3V GPIO7 (NOT 5V tolerant)
12 IO8 GPIO8 mixed GPIO8 ADC1_CH7 TOUCH8
General-purpose 3.3V GPIO8 (NOT 5V tolerant)
13 IO9 GPIO9 mixed GPIO9 ADC1_CH8 TOUCH9
General-purpose 3.3V GPIO9 (NOT 5V tolerant)
14 IO10 GPIO10 mixed GPIO10 ADC1_CH9 TOUCH10 FSPICS0
General-purpose 3.3V GPIO10 (NOT 5V tolerant)
15 IO11 GPIO11 mixed GPIO11 ADC2_CH0 TOUCH11 FSPID
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO11 (NOT 5V tolerant)
16 IO12 GPIO12 mixed GPIO12 ADC2_CH1 TOUCH12 FSPICLK
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO12 (NOT 5V tolerant)
17 IO13 GPIO13 mixed GPIO13 ADC2_CH2 TOUCH13 FSPIQ
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO13 (NOT 5V tolerant)
18 IO14 GPIO14 mixed GPIO14 ADC2_CH3 TOUCH14
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO14 (NOT 5V tolerant)
19 IO15 GPIO15 mixed GPIO15 ADC2_CH4 XTAL_32K_P
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO15 (NOT 5V tolerant)
20 IO16 GPIO16 mixed GPIO16 ADC2_CH5 XTAL_32K_N
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO16 (NOT 5V tolerant)
21 IO17 GPIO17 mixed GPIO17 ADC2_CH6 DAC_1 U1TXD
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO17 (NOT 5V tolerant)
22 IO18 GPIO18 mixed GPIO18 ADC2_CH7 DAC_2 U1RXD
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
General-purpose 3.3V GPIO18 (NOT 5V tolerant)
23 IO19 GPIO19 mixed GPIO19 ADC2_CH8 USB_D-
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
[INFO] Native Full-Speed USB OTG 1.1 differential pair (D- / D+)
Reconfiguring GPIO19/GPIO20 as digital I/O disconnects native USB CDC/DFU.
General-purpose 3.3V GPIO19 (NOT 5V tolerant)
24 IO20 GPIO20 mixed GPIO20 ADC2_CH9 USB_D+
[CAUTION] ADC2 channel restricted during Wi-Fi transmission
Prefer ADC1 (GPIO1–GPIO10) for analog reads when Wi-Fi is active.
[INFO] Native Full-Speed USB OTG 1.1 differential pair (D- / D+)
Reconfiguring GPIO19/GPIO20 as digital I/O disconnects native USB CDC/DFU.
General-purpose 3.3V GPIO20 (NOT 5V tolerant)
25 IO21 GPIO21 digital GPIO21
General-purpose 3.3V GPIO21 (NOT 5V tolerant)
26 IO26 GPIO26 digital GPIO26 SPICS1
[CAUTION] SPICS1 — reserved for PSRAM CE# on -R2 / -FN4R2 / -N4R2 variants
Usable as GPIO26 only on non-PSRAM variants; internally bonded to 2 MB PSRAM CE# on PSRAM-equipped chips and modules.
[DANGER] Reserved for internal 2 MB PSRAM CE# on -N4R2 variants — leave unconnected on -N4R2!
Available as GPIO26 ONLY on non-PSRAM -N4 modules. On ESP32-S2-MINI-2-N4R2 / MINI-2U-N4R2, Pin 26 is internally wired to PSRAM SPICS1.
General-purpose 3.3V GPIO26 (NOT 5V tolerant)
27 NC nc —
No internal connection — leave floating on host PCB
28 IO33 GPIO33 digital GPIO33
General-purpose 3.3V GPIO33 (NOT 5V tolerant)
29 IO34 GPIO34 digital GPIO34
General-purpose 3.3V GPIO34 (NOT 5V tolerant)
30 GND ground GND
Module system ground (0V)
31 IO35 GPIO35 digital GPIO35
General-purpose 3.3V GPIO35 (NOT 5V tolerant)
32 IO36 GPIO36 digital GPIO36
General-purpose 3.3V GPIO36 (NOT 5V tolerant)
33 IO37 GPIO37 digital GPIO37
General-purpose 3.3V GPIO37 (NOT 5V tolerant)
34 IO38 GPIO38 digital GPIO38
General-purpose 3.3V GPIO38 (NOT 5V tolerant)
35 IO39 GPIO39 digital GPIO39 MTCK
General-purpose 3.3V GPIO39 (NOT 5V tolerant)
36 IO40 GPIO40 digital GPIO40 MTDO
General-purpose 3.3V GPIO40 (NOT 5V tolerant)
37 IO41 GPIO41 digital GPIO41 MTDI
General-purpose 3.3V GPIO41 (NOT 5V tolerant)
38 IO42 GPIO42 digital GPIO42 MTMS
General-purpose 3.3V GPIO42 (NOT 5V tolerant)
39 TXD0 GPIO43 digital GPIO43 U0TXD
General-purpose 3.3V GPIO43 (NOT 5V tolerant)
40 RXD0 GPIO44 digital GPIO44 U0RXD
General-purpose 3.3V GPIO44 (NOT 5V tolerant)
41 IO45 GPIO45 digital GPIO45
[DANGER] VDD_SPI flash voltage strap (weak pull-down: LOW=3.3V, HIGH=1.8V)
Pulling GPIO45 HIGH at reset switches VDD_SPI to 1.8V, preventing 3.3V flash/PSRAM parts from booting.
General-purpose 3.3V GPIO45 (NOT 5V tolerant)
42 GND ground GND
Module system ground (0V)
43 GND ground GND
Module system ground (0V)
44 IO46 GPIO46 digital GPIO46
[CAUTION] Input-only strapping pin (fixed internal pull-down; NO output driver!)
On ESP32-S2, GPIO46 has no output buffer and cannot drive signals high or low. Also sampled at reset for boot mode & ROM log printing (keep LOW at reset).
Input-only strapping pin GPIO46 (no output driver, internal pull-down)
45 EN CHIP_PU reset CHIP_PU
[CAUTION] Active-HIGH chip enable / reset — never leave floating
Add an external 10 kΩ pull-up to 3.3V and 1 µF capacitor to GND.
Active-HIGH chip enable / reset input (EN / CHIP_PU)
46-65 GND ground GND
Underside 20-pad thermal & RF ground array (Pads 46–65; connect to host GND)