ESP32-C3
Ultra-low-power RISC-V processor
- Processor
- Single-core
- Up to 160 MHz
- SRAM
- 400 KB
- + 8 KB RTC SRAM
- GPIO
- 22
- programmable pins
- Architecture
- RISC-V
- RISC-V single-core 32-bit
Official development kit
Official Espressif board for the ESP32-C3 series.
Pins with usage restrictions
Not every pin on the ESP32-C3 is free for general-purpose use. 18 of them have conditions: occupied by memory, sampled during boot, or function as input only. Check before finalizing your schematic.
Connected to flash/PSRAM memory
6 pins- SPIHD · GPIO12
- SPIWP · GPIO13
- SPICS0 · GPIO14
- SPICLK · GPIO15
- SPID · GPIO16
- SPIQ · GPIO17
Already connected to the memory where firmware is stored and executed. Using them as general-purpose GPIO typically crashes the chip or corrupts execution. In modules with internal flash, they are not brought out to the package pins.
Strapping pins (boot mode)
3 pins- GPIO2
- GPIO8
- GPIO9
The chip samples the logic level of these pins during reset to determine the boot mode. You can use them after booting, but external circuitry must not force the wrong level during reset, or the board will fail to boot or enter download mode unexpectedly.
Flashing and debugging
6 pins- MTMS · GPIO4
- MTDI · GPIO5
- MTCK · GPIO6
- MTDO · GPIO7
- U0RXD · GPIO20
- U0TXD · GPIO21
These are the flashing UART and JTAG lines. They can still be used as GPIO, but reusing them removes the ability to flash and debug the board without disconnecting connected peripherals.
Native USB
2 pins- GPIO18
- GPIO19
Connected by default to the internal USB Serial/JTAG controller. Using them as GPIO requires disabling this peripheral, which also removes direct USB flashing.
Must not float
1 pin- CHIP_EN
Require a defined hardware logic level: external pull-up or RC delay circuit. Leaving them floating causes random resets or unstable boot behavior.
These groups are derived from the same data as the pinout diagram. There you can see every pin's full functions, power domain, and complete engineering notes.
Open pinout diagramProcessor
- Architecture
- RISC-V single-core 32-bit
- Cores
- 1 (Single-core)
- Frequency
- Up to 160 MHz
- ULP Coprocessor
- No
- AI Accelerators
- No
Connectivity
- Wi-Fi
- IEEE 802.11 b/g/n (2.4 GHz, up to 150 Mbps)
- Bluetooth
- Bluetooth 5 (LE) and Bluetooth Mesh
- Zigbee/Thread
- No
- Matter
- No
- Ethernet
- No
- CAN
- No
Tools and availability
- Minimum ESP-IDF
- v4.3
- Arduino Core
- Yes (29 board definitions in official core)
- Debugging
- Integrated JTAG via USB (no external probe required)
- Package
- QFN32 (5×5 mm) and QFN28 (4×4 mm)
- Available Modules
- ESP32-C3-MINI-1, ESP32-C3-WROOM-02
Security
- AES
- AES-128/256
- SHA
- SHA-1/224/256
- RSA / MPI
- Yes (RSA/MPI up to 3072 bits)
- ECC (elliptic curves)
- No
- Hardware ECDSA
- No
- HMAC
- Yes
- Digital Signature (DS)
- Yes
- Key Manager
- No
- Random Generator (TRNG)
- Yes (hardware TRNG)
- Flash Encryption
- XTS-AES-128
- Secure Boot
- V2 (RSA-3072), starting from rev v0.3 (ECO3)
- DPA Protection
- No
Memory
- SRAM
- 400 KB
- RTC SRAM
- 8 KB
- ROM
- 384 KB
- External Flash
- Up to 16 MB via QSPI
- External PSRAM
- No
Power consumption
Typical values at 3.3 V and 25 °C. Actual power consumption depends on radio duty cycle and configured clock frequency.
- Active (CPU 160MHz)
- 20 mA
- Active (Wi-Fi TX Peak)
- 335 mA
- Modem Sleep (CPU 160MHz)
- 16-28 mA
- Light Sleep
- 130 µA
- Deep Sleep
- 5 µA
Peripherals
- GPIO
- 22
- ADC
- 2x 12-bit SAR ADC, up to 6 channels
- DAC
- No
- Touch
- No
- UART
- 2
- SPI
- 3 (SPI0/1 for Flash, SPI2 for general use)
- I2C
- 1
- I2S
- 1
- PWM
- LED PWM (up to 6 channels)
- USB
- 1 (USB Serial/JTAG)
Special interfaces
- Temperature Sensor
- 1 (internal)
Temperature limits
- Operating
- -40°C to 105°C (85°C on ESP32-C3FN4)
- Storage
- -40°C to 150°C
Ready to prototype with ESP32-C3?
Explore development boards available for this series, with USB, onboard sensors, and official store links.