ProS3 - ESP32-S3 Development Board by Unexpected Maker

Long-form ESP32-S3 development board with dual-core 240 MHz LX7, 16 MB flash, 8 MB PSRAM, USB-C native USB + JTAG, 2.4 GHz Wi-Fi, BT 5/BLE, LiPo charging, STEMMA connector, and castellated headers. Ships with CircuitPython and UF2 bootloader.

Logical pinout · physical placement not verified

VBAT1
LiPo battery input from the ProS3 board header, source-backed by the official Unexpected Maker ProS3 KiCad symbol.
Type · Power
GND2
Ground reference on the ProS3 board header.
Type · Ground
5V3
5 V rail/header pin on the ProS3 board; product page also states USB-C with back-feed protection and 5V sense support.
Type · PowerVoltage · 5V
3V34
3.3 V regulated rail/header pin on the ProS3 board.
Type · PowerVoltage · 3.3V
IO15
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO26
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO37
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO48
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO59
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO2110
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO011
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface, commonly used as a boot/control GPIO on ESP32-S3 boards.
Type · GPIO
LDO2_OUT12
Secondary LDO output exposed by the ProS3 KiCad symbol.
Type · Power
IO1613
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO1514
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO1415
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO1316
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO1217
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO4218
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO4119
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO4020
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3921
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3822
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
RX23
UART receive pin exposed on the ProS3 board header.
Type · UART
TX24
UART transmit pin exposed on the ProS3 board header.
Type · UART
GND25
Second ground reference pin on the ProS3 board header.
Type · Ground
RST26
Reset input exposed on the ProS3 board header.
Type · Control
IO627
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO728
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO829
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO930
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3431
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3632
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3733
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
IO3534
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
Type · GPIO
USB-C
USB-C connector provides native USB and USB serial/JTAG per the Adafruit/Unexpected Maker product page.
Type · USB
STEMMA QT
STEMMA QT connector is present and powered by LDO1 per the official ProS3 product page.
Type · I2C
LiPo PicoBlade
LiPo battery charging connector on the ProS3 board per the official product page.
Type · Power

Pin	Position	Type	Function	Voltage
VBAT	1	Power	LiPo battery input from the ProS3 board header, source-backed by the official Unexpected Maker ProS3 KiCad symbol.
GND	2	Ground	Ground reference on the ProS3 board header.
5V	3	Power	5 V rail/header pin on the ProS3 board; product page also states USB-C with back-feed protection and 5V sense support.	5V
3V3	4	Power	3.3 V regulated rail/header pin on the ProS3 board.	3.3V
IO1	5	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO2	6	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO3	7	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO4	8	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO5	9	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO21	10	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO0	11	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface, commonly used as a boot/control GPIO on ESP32-S3 boards.
LDO2_OUT	12	Power	Secondary LDO output exposed by the ProS3 KiCad symbol.
IO16	13	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO15	14	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO14	15	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO13	16	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO12	17	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO42	18	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO41	19	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO40	20	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO39	21	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO38	22	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
RX	23	UART	UART receive pin exposed on the ProS3 board header.
TX	24	UART	UART transmit pin exposed on the ProS3 board header.
GND	25	Ground	Second ground reference pin on the ProS3 board header.
RST	26	Control	Reset input exposed on the ProS3 board header.
IO6	27	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO7	28	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO8	29	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO9	30	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO34	31	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO36	32	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO37	33	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
IO35	34	GPIO	ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
USB-C		USB	USB-C connector provides native USB and USB serial/JTAG per the Adafruit/Unexpected Maker product page.
STEMMA QT		I2C	STEMMA QT connector is present and powered by LDO1 per the official ProS3 product page.
LiPo PicoBlade		Power	LiPo battery charging connector on the ProS3 board per the official product page.

Logical pinout · physical placement not verified

Pin details

37 connections

VBAT
LiPo battery input from the ProS3 board header, source-backed by the official Unexpected Maker ProS3 KiCad symbol.
Power
1
GND
Ground reference on the ProS3 board header.
Ground
2
5V
5 V rail/header pin on the ProS3 board; product page also states USB-C with back-feed protection and 5V sense support.
PowerVoltage · 5V
3
3V3
3.3 V regulated rail/header pin on the ProS3 board.
PowerVoltage · 3.3V
4
IO1
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
5
IO2
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
6
IO3
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
7
IO4
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
8
IO5
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
9
IO21
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
10
IO0
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface, commonly used as a boot/control GPIO on ESP32-S3 boards.
GPIO
11
LDO2_OUT
Secondary LDO output exposed by the ProS3 KiCad symbol.
Power
12
IO16
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
13
IO15
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
14
IO14
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
15
IO13
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
16
IO12
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
17
IO42
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
18
IO41
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
19
IO40
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
20
IO39
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
21
IO38
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
22
RX
UART receive pin exposed on the ProS3 board header.
UART
23
TX
UART transmit pin exposed on the ProS3 board header.
UART
24
GND
Second ground reference pin on the ProS3 board header.
Ground
25
RST
Reset input exposed on the ProS3 board header.
Control
26
IO6
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
27
IO7
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
28
IO8
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
29
IO9
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
30
IO34
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
31
IO36
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
32
IO37
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
33
IO35
ESP32-S3 GPIO exposed on the ProS3 castellated/header interface.
GPIO
34
USB-C
USB-C connector provides native USB and USB serial/JTAG per the Adafruit/Unexpected Maker product page.
USB
STEMMA QT
STEMMA QT connector is present and powered by LDO1 per the official ProS3 product page.
I2C
LiPo PicoBlade
LiPo battery charging connector on the ProS3 board per the official product page.
Power

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