ESP32-DevKitC V4 is a small-sized ESP32-based development board produced by Espressif. Most of the I/O pins are broken out to the pin headers on both sides for easy interfacing. Developers can either connect peripherals with jumper wires or mount ESP32-DevKitC V4 on a breadboard.
The below is an extract from the manufacturer’s website, available at this LINK:
Functional Description
| Key Component | Description |
|---|---|
| ESP32-WROOM-32 | A module with ESP32 at its core. For more information, see ESP32-WROOM-32 Datasheet. |
| EN | Reset button. |
| Boot | Download button. Holding down Boot and then pressing EN initiates Firmware Download mode for downloading firmware through the serial port. |
| USB-to-UART Bridge | Single USB-UART bridge chip provides transfer rates of up to 3 Mbps. |
| Micro USB Port | USB interface. Power supply for the board as well as the communication interface between a computer and the ESP32-WROOM-32 module. |
| 5V Power On LED | Turns on when the USB or an external 5V power supply is connected to the board. For details see the schematics in Related Documents. |
| I/O | Most of the pins on the ESP module are broken out to the pin headers on the board. You can program ESP32 to enable multiple functions such as PWM, ADC, DAC, I2C, I2S, SPI, etc. |
Power Supply Options
There are three mutually exclusive ways to provide power to the board:
- Micro USB port, default power supply
- 5V / GND header pins
- 3V3 / GND header pins
Warning
The power supply must be provided using one and only one of the options above, otherwise the board and/or the power supply source can be damaged.
Header Block
The two tables below provide the Name and Function of I/O header pins on both sides of the board, as shown in ESP32-DevKitC V4 with ESP32-WROOM-32 module soldered.
J2
| No. | Name | Type 1 | Function |
|---|---|---|---|
| 1 | 3V3 | P | 3.3 V power supply |
| 2 | EN | I | CHIP_PU, Reset |
| 3 | VP | I | GPIO36, ADC1_CH0, S_VP |
| 4 | VN | I | GPIO39, ADC1_CH3, S_VN |
| 5 | IO34 | I | GPIO34, ADC1_CH6, VDET_1 |
| 6 | IO35 | I | GPIO35, ADC1_CH7, VDET_2 |
| 7 | IO32 | I/O | GPIO32, ADC1_CH4, TOUCH_CH9, XTAL_32K_P |
| 8 | IO33 | I/O | GPIO33, ADC1_CH5, TOUCH_CH8, XTAL_32K_N |
| 9 | IO25 | I/O | GPIO25, ADC1_CH8, DAC_1 |
| 10 | IO26 | I/O | GPIO26, ADC2_CH9, DAC_2 |
| 11 | IO27 | I/O | GPIO27, ADC2_CH7, TOUCH_CH7 |
| 12 | IO14 | I/O | GPIO14, ADC2_CH6, TOUCH_CH6, MTMS |
| 13 | IO12 | I/O | GPIO12, ADC2_CH5, TOUCH_CH5, MTDI |
| 14 | GND | G | Ground |
| 15 | IO13 | I/O | GPIO13, ADC2_CH4, TOUCH_CH4, MTCK |
| 16 | D2 | I/O | GPIO9, D2 2 |
| 17 | D3 | I/O | GPIO10, D3 2 |
| 18 | CMD | I/O | GPIO11, CMD 2 |
| 19 | 5V | P | 5 V power supply |
J3
| No. | Name | Type 1 | Function |
|---|---|---|---|
| 1 | GND | G | Ground |
| 2 | IO23 | I/O | GPIO23 |
| 3 | IO22 | I/O | GPIO22 |
| 4 | TX | I/O | GPIO1, U0TXD |
| 5 | RX | I/O | GPIO3, U0RXD |
| 6 | IO21 | I/O | GPIO21 |
| 7 | GND | G | Ground |
| 8 | IO19 | I/O | GPIO19 |
| 9 | IO18 | I/O | GPIO18 |
| 10 | IO5 | I/O | GPIO5 |
| 11 | IO17 | I/O | GPIO17 3 |
| 12 | IO16 | I/O | GPIO16 3 |
| 13 | IO4 | I/O | GPIO4, ADC2_CH0, TOUCH_CH0 |
| 14 | IO0 | I/O | GPIO0, ADC2_CH1, TOUCH_CH1, Boot |
| 15 | IO2 | I/O | GPIO2, ADC2_CH2, TOUCH_CH2 |
| 16 | IO15 | I/O | GPIO15, ADC2_CH3, TOUCH_CH3, MTDO |
| 17 | D1 | I/O | GPIO8, D1 2 |
| 18 | D0 | I/O | GPIO7, D0 2 |
| 19 | CLK | I/O | GPIO6, CLK 2 |
- 1(1,2)
- P: Power supply; I: Input; O: Output.
- 2(1,2,3,4,5,6)
- The pins D0, D1, D2, D3, CMD and CLK are used internally for communication between ESP32 and SPI flash memory. They are grouped on both sides near the USB connector. Avoid using these pins, as it may disrupt access to the SPI flash memory / SPI RAM.
- 3(1,2)
- The pins GPIO16 and GPIO17 are available for use only on the boards with the modules ESP32-WROOM and ESP32-SOLO-1. The boards with ESP32-WROVER modules have the pins reserved for internal use.
Pin Layout
Note on C15
The component C15 may cause the following issues on earlier ESP32-DevKitC V4 boards:
- The board may boot into Download mode
- If you output clock on GPIO0, C15 may impact the signal
In case these issues occur, please remove the component. The figure below shows the location of C15 highlighted in yellow.
