esp-dev-kits Choose target... Choose version... ESP32-S31 Boards ESP32-S31-Function-CoreBoard-1 ESP32-S31-Korvo-1 User Guide Resources and Legal Notices Related Documentation and Resources Disclaimer and Copyright Notice esp-dev-kits ESP32-S31-Korvo-1 Download PDF ESP32-S31-Korvo-1 [中文] The ESP32-S31-Korvo-1 is a multimedia development board based on the ESP32-S31-WROOM-3 module for smart audio and HMI applications. It features a dual-microphone array, speaker output, and a microSD card slot; supports speech recognition and voice wake-up; and can connect to a 4.3-inch LCD subboard and DVP camera. This document describes revision V1.1. User Guide Getting Started Hardware Reference Hardware Revision Details Related Documents Disclaimer and Copyright Notice Next Previous Suggestion on this document? Provide feedback Help improve this document? Edit on GitHub Need more information? Check ESP forum Sales Questions Technical Inquiries © Copyright 2016 - 2026, Espressif Systems (Shanghai) CO., LTD Built with Sphinx using a theme based on Read the Docs Sphinx Theme. esp-dev-kits Choose target... Choose version... ESP32-S31 Boards ESP32-S31-Function-CoreBoard-1 ESP32-S31-Korvo-1 Resources and Legal Notices Related Documentation and Resources Disclaimer and Copyright Notice Terms of Use for Development Board esp-dev-kits Disclaimer and Copyright Notice Download PDF Disclaimer and Copyright Notice [中文] Information in this document, including URL references, is subject to change without notice. All third party’s information in this document is provided as is with no warranties to its authenticity and accuracy. No warranty is provided to this document for its merchantability, non-infringement, fitness for any particular purpose, nor does any warranty otherwise arising out of any proposal, specification or sample. All liability, including liability for infringement of any proprietary rights, relating to use of information in this document is disclaimed. No licenses express or implied, by estoppel or otherwise, to any intellectual property rights are granted herein. The Wi-Fi Alliance Member logo is a trademark of the Wi-Fi Alliance. The Bluetooth logo is a registered trademark of Bluetooth SIG. All trade names, trademarks and registered trademarks mentioned in this document are property of their respective owners, and are hereby acknowledged. Terms of Use for Development Board The development board is intended for R&D evaluation, engineering design verification, and early-stage product development. It is provided as a convenient platform for development and testing. The development board is not intended as a mass-production component or as a finished product for end consumers; therefore, its product management approach differs from that of mass-produced chips and modules. The development board has not obtained specific national or industry certifications and is not covered under regulatory frameworks such as CE, UL, or CCC. As a result, it may not meet the requirements of such regulations. Users should ensure that their use of the development board complies with the applicable laws and regulations of the country or region in which it is used. In addition, the development board has not been designed, validated, or managed for reliability testing, production, or commercial deployment purposes. Users assume full responsibility for the correct and safe use of the product. For applications beyond the intended use of the development board, including but not limited to pre-production testing, system integration, final product delivery, or other commercial uses, the user should, before mass production and in light of its own product requirements, fully evaluate the technical suitability, reliability requirements, regulatory compliance, and system integration risks associated with such applications. The user should also complete all necessary verification, testing, and certification activities relating to system-level design, product certification, reliability validation, regulatory compliance assessment, and commercial deployment. Espressif assumes no liability arising from applications beyond the intended use of the development board. Regardless of whether the parties have entered into a supplier framework agreement, quality agreement, or any other similar agreement, the development board is not subject to any requirements or commitments therein relating to product certification, reliability management, return material analysis (RMA), product/process change notification (PCN), end-of-life (EOL) management, long-term supply commitments, or any other requirements and commitments established under a mass-production product management model. Previous Suggestion on this document? Provide feedback Help improve this document? Edit on GitHub Need more information? Check ESP forum Sales Questions Technical Inquiries © Copyright 2016 - 2026, Espressif Systems (Shanghai) CO., LTD Built with Sphinx using a theme based on Read the Docs Sphinx Theme. esp-dev-kits Choose target... Choose version... ESP32-S31 Boards ESP32-S31-Function-CoreBoard-1 ESP32-S31-Korvo-1 User Guide Getting Started Description of Components Development Board Accessories Start Application Development Contents and Packaging Hardware Reference Block Diagram Power Supply Description ES8389 Audio Codec Notes microSD Card and SPI NAND Flash Pin Assignment Table Hardware Setup Options Hardware Revision Details Related Documents Disclaimer and Copyright Notice Resources and Legal Notices Related Documentation and Resources Disclaimer and Copyright Notice esp-dev-kits ESP32-S31-Korvo-1 ESP32-S31-Korvo-1 V1.1 Download PDF ESP32-S31-Korvo-1 V1.1 [中文] This user guide will help you get started with ESP32-S31-Korvo-1 V1.1 and provides detailed information about this development board. The ESP32-S31-Korvo-1 V1.1 is a multimedia development board based on the ESP32-S31-WROOM-3 module for smart audio and HMI applications. It features a dual-microphone array, speaker output, and a microSD card slot; supports speech recognition and voice wake-up; and can connect to a 4.3-inch LCD subboard and DVP camera. ESP32-S31-Korvo-1 V1.1 (with ESP32-S31-WROOM-3 module on board) The document consists of the following major sections: Getting Started: Overview of ESP32-S31-Korvo-1 V1.1 and hardware/software setup instructions to get started. Hardware Reference: More detailed information about the ESP32-S31-Korvo-1 V1.1 hardware. Hardware Revision Details: Information about revision history, known issues, and links to user guides for previous versions. Related Documents: Links to related documentation. Disclaimer and Copyright Notice: Link to the disclaimer and copyright notice. Getting Started This section briefly introduces ESP32-S31-Korvo-1 V1.1 and explains how to perform the initial hardware setup and how to flash firmware onto the board. Description of Components ESP32-S31-Korvo-1 V1.1 (click to enlarge) The following list describes the key components on the board in a clockwise direction. No. Component Description 1 USB Type-C Port (Power) Power input only; no data communication. 2 USB Type-C Port (UART) Can power the board, flash firmware to the chip, and communicate with the ESP32-S31 via the onboard USB-to-UART bridge. 3 USB-to-UART Bridge Single-chip USB-to-UART bridge supporting up to 3 Mbps. 4 Power Switch Slide toward ON to apply 5 V power; slide away from ON to disconnect 5 V power. 5 USB 2.0 Type-A Port Connected to the ESP32-S31 USB 2.0 OTG High-Speed interface and supports the USB 2.0 standard. When used for USB communication, ESP32-S31 acts as a USB Host connected to downstream USB devices, providing up to 500 mA output current. 6 Buck Converter Buck DC-DC converter for 3.3 V system power. 7 5 V Power-on LED Lights when USB power is connected to the board. 8 Switch TPS2051C USB power switch with 500 mA current limit. 9 Right Speaker Output Port Right-channel speaker output; can drive a 4 Ω, 3 W speaker. The pin spacing is 2.00 mm (0.08”). 10 Right Microphone Onboard right analog microphone routed to the audio codec. 11 5 V to 3.3 V LDO Converts 5 V to 3.3 V for the audio circuitry. 12 Right Audio PA Chip NS4150B low-EMI 3 W mono class-D amplifier driving the right speaker from the codec output. 13 Function Buttons Four buttons: PLAY, SET, VOL-, and VOL+, connected to ESP32-S31-WROOM-3 for UI control and audio application testing via dedicated APIs. 14 Audio Codec Chip ES8389 low-power stereo codec with dual ADC/DAC, low-noise preamp, headphone driver, digital effects, analog mixing, and gain control. Connected to the ESP32-S31 over I2S and I2C for hardware audio processing independent of application software. 15 Left Audio PA Chip NS4150B low-EMI 3 W mono class-D amplifier driving the left speaker from the codec output. 16 Left Microphone Onboard left analog microphone routed to the audio codec. 17 Left Speaker Output Port Left-channel speaker output; can drive a 4 Ω, 3 W speaker. The pin spacing is 2.00 mm (0.08”). 18 RGB LED Addressable RGB LED driven by GPIO8. No. Component Description 19 3.3 V to 1.8 V LDO (NC) Converts 3.3 V to 1.8 V for 1.8 V SPI NAND flash. Not populated by default (NC). 20 SPI NAND Flash (NC) Quad SPI NAND flash sharing ESP32-S31-WROOM-3 signals with the microSD interface. Not populated by default (NC). 21 LCD Connector Connector for the LCD subboard. 22 ESP32-S31-WROOM-3 ESP32-S31-WROOM-3 is a general-purpose module supporting 2.4 GHz Wi-Fi 6, Bluetooth 5.4, Bluetooth Classic, and IEEE 802.15.4 (Zigbee 3.0 and Thread 1.4). The module integrates ESP32-S31, 16 MB SPI flash, and 16 MB PSRAM, and uses an onboard PCB antenna. 23 microSD Card Slot Supports 4-bit microSD for audio storage and playback. SDIO 3.0 capable. 24 3.3 V to 2.8 V LDO Converts 3.3 V to 2.8 V for the external camera module. 25 3.3 V to 1.5 V LDO Converts 3.3 V to 1.5 V for the external camera module. 26 Camera Connector Connector for an external camera module for image transfer. 27 Reset