1 Module Overview 1.1 Features 1.2 Series Comparison 1.3 Applications 2 Block Diagram 3 Pin Definitions 3.1 Pin Layout 3.2 Pin Description 4 Boot Configurations 4.1 Chip Boot Mode Control 4.2 VDD_SPI Voltage Control 4.3 ROM Messages Printing Control 4.4 Chip Power-up and Reset 5 Electrical Characteristics 5.1 Absolute Maximum Ratings 5.2 Recommended Operating Conditions 5.3 DC Characteristics (3.3 V, 25 °C) 5.4 Current Consumption Characteristics 5.4.1 Current Consumption in Active Mode 5.4.2 Current Consumption in Other Modes 5.5 Memory Specifications 6 RF Characteristics 6.1 Wi-Fi Radio 6.1.1 Wi-Fi RF Standards 6.1.2 Wi-Fi RF Transmitter (TX) Specifications 6.1.3 Wi-Fi RF Receiver (RX) Specifications 7 Module Schematics 8 Peripheral Schematics 9 Physical Dimensions 9.1 Module Dimensions 9.2 Dimensions of External Antenna Connector 10 PCB Layout Recommendations 10.1 PCB Land Pattern 10.2 Module Placement for PCB Design 11 Product Handling 11.1 Storage Conditions 11.2 Electrostatic Discharge (ESD) 11.3 Soldering Profiles 11.3.1 Reflow Profile 11.3.2 Wave Profile 11.4 Ultrasonic Vibration Datasheet Versioning Related Documentation and Resources Revision History ESP32-S2-SOLO-2 ESP32-S2-SOLO-2U Datasheet Version 1.4 2.4 GHz Wi-Fi (802.11 b/g/n) module Built around ESP32-S2 series of SoC, Xtensa ® single-core 32-bit LX7 microprocessor Flash up to 16 MB, optional 2 MB PSRAM in chip package 36 GPIOs, rich set of peripherals On-board PCB antenna or external antenna connector ESP32-S2-SOLO-2 ESP32-S2-SOLO-2U www.espressif.com 1 Module Overview 1 Module Overview Note: Check the link or the QR code to make sure that you use the latest version of this document: https://espressif.com/documentation/esp32-s2-solo-2_esp32-s2-solo-2u_datasheet_en.pdf 1.1 Features CPU and On-Chip Memory • ESP32-S2 or ESP32-S2R2 embedded, Xtensa ® single-core 32-bit LX7 microprocessor, up to 240 MHz • 128 KB ROM • 320 KB SRAM • 16 KB SRAM in RTC • 2 MB PSRAM (ESP32-S2R2 only) Wi-Fi • 802.11b/g/n • Bit rate: 802.11n up to 150 Mbps • A-MPDU and A-MSDU aggregation • 0.4 µs guard interval support • Center frequency range of operating channel: 2412 ~ 2484 MHz Peripherals • Up to 36 GPIOs • SPI, LCD, UART, I2C, I2S, Camera interface, IR, pulse counter, LED PWM, TWAI ® (compatible with ISO 11898-1, i.e. CAN Specification 2.0), full-speed USB OTG, ADC, DAC, touch sensor, temperature sensor, general-purpose timers, watchdog timers Note: * Please refer to ESP32-S2 Series Datasheet for detailed information about the module peripherals. Integrated Components on Module • 40 MHz crystal oscillator • Quad SPI flash up to 16 MB Antenna Options • ESP32-S2-SOLO-2: On-board PCB antenna • ESP32-S2-SOLO-2U: External antenna via a connector Operating Conditions • Operating voltage/Power supply: 3.0 ~ 3.6 V • Operating ambient temperature: – 85 °C version: –40 ~ 85 °C – 105 °C version: –40 ~ 105 °C (ESP32-S2-SOLO-2-H4 and ESP32-S2-SOLO-2U-H4 only) Certification • RF certification: See certificates • Green certification: RoHS/REACH Test • HTOL/HTSL/uHAST/TCT/ESD/Latch-up Espressif Systems 2 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 1 Module Overview 1.2 Series Comparison ESP32-S2-SOLO-2 and ESP32-S2-SOLO-2U are two powerful, generic Wi-Fi MCU modules that have a rich set of peripherals. They are an ideal choice for a wide variety of application scenarios relating to Internet of Things (IoT), wearable electronics and smart home. ESP32-S2-SOLO-2 comes with a PCB antenna (ANT). ESP32-S2-SOLO-2U comes with an external antenna connector (CONN). A wide selection of module variants are available. The variant nomenclature is shown in Figure 1-1, and the series comparisons are listed in Table 1-1 and Table 1-2. The nomenclature for the module variants is as follows: ESP32-S2 -XX-XX H/N x R Flash size (MB) Ambient temperature (℃) H：-40 ~ 105 N：-40 ~ 85 Module name x PSRAM size (MB) PSRAM (optional) Figure 1-1. ESP32-S2 Module Variant Nomenclature Espressif Systems 3 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 1 Module Overview Table 1-1. ESP32-S2-SOLO-2 (ANT) Series Comparison Ambient Temp. 1 Size 2 Part Number Flash 3 PSRAM 3 (°C) (mm) ESP32-S2-SOLO-2-N4 4 MB (Quad SPI) — –40 ∼ 85 18.0 × 25.5 × 3.1 ESP32-S2-SOLO-2-H4 (End of life) — –40 ∼ 105 ESP32-S2-SOLO-2-N4R2 2 MB (Quad SPI) –40 ∼ 85ESP32-S2-SOLO-2-N8 (End of life) 8 MB (Quad SPI) — ESP32-S2-SOLO-2-N16 16 MB (Quad SPI) — 1 Ambient temperature specifies the recommended temperature range of the environment immediately outside the Espressif module. 2 For details, refer to Section 9.1 Module Dimensions. 3 For specifications, refer to Section 5.5 Memory Specifications. Table 1-2. ESP32-S2-SOLO-2U (CONN) Series Comparison 1 Ambient Temp. Size Part Number Flash PSRAM (°C) (mm) ESP32-S2-SOLO-2U-N4 4 MB (Quad SPI) — –40 ∼ 85 18.0 × 19.2 × 3.2 ESP32-S2-SOLO-2U-H4 — –40 ∼ 105 ESP32-S2-SOLO-2U-N4R2 2 MB (Quad SPI) –40 ∼ 85 ESP32-S2-SOLO-2U-N16 16 MB (Quad SPI) — 4 This table shares the same notes presented in Table 1-1 above. In this datasheet unless otherwise stated, ESP32-S2-SOLO-2 refers to all variants of ESP32-S2-SOLO-2, whereas ESP32-S2-SOLO-2U refers to all variants of ESP32-S2-SOLO-2U. At the core of the modules is ESP32-S2 series chip revision v1.0. ESP32-S2 series of chips has an Xtensa® 32-bit LX7 CPU that operates at up to 240 MHz. It has a low-power co-processor that can be used instead of the CPU to save power while performing tasks that do not require much computing power, such as monitoring of peripherals. Note: For more information on ESP32-S2R2, please refer to ESP32-S2 Series Datasheet. For chip revision identification, ESP-IDF release that supports a specific chip revision, and other information on chip revisions, please refer to ESP32-S2 Series SoC Errata > Section Chip Revision. 1.3 Applications • Smart Home • Industrial Automation • Health Care • Consumer Electronics • Smart Agriculture • POS Machines • Service Robot • Audio Devices Espressif Systems 4 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 1 Module Overview • Generic Low-power IoT Sensor Hubs • Generic Low-power IoT Data Loggers • Cameras for Video Streaming • USB Devices • Speech Recognition • Image Recognition • Wi-Fi + Bluetooth Networking Card • Touch and Proximity Sensing Espressif Systems 5 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Contents Contents 1 Module Overview 2 1.1 Features 2 1.2 Series Comparison 3 1.3 Applications 4 2 Block Diagram 10 3 Pin Definitions 11 3.1 Pin Layout 11 3.2 Pin Description 11 4 Boot Configurations 14 4.1 Chip Boot Mode Control 15 4.2 VDD_SPI Voltage Control 15 4.3 ROM Messages Printing Control 16 4.4 Chip Power-up and Reset 16 5 Electrical Characteristics 18 5.1 Absolute Maximum Ratings 18 5.2 Recommended Operating Conditions 18 5.3 DC Characteristics (3.3 V, 25 °C) 18 5.4 Current Consumption Characteristics 19 5.4.1 Current Consumption in Active Mode 19 5.4.2 Current Consumption in Other Modes 19 5.5 Memory Specifications 20 6 RF Characteristics 22 6.1 Wi-Fi Radio 22 6.1.1 Wi-Fi RF Standards 22 6.1.2 Wi-Fi RF Transmitter (TX) Specifications 22 6.1.3 Wi-Fi RF Receiver (RX) Specifications 23 7 Module Schematics 25 8 Peripheral Schematics 27 9 Physical Dimensions 28 9.1 Module Dimensions 28 9.2 Dimensions of External Antenna Connector 29 10 PCB Layout Recommendations 31 10.1 PCB Land Pattern 31 10.2 Module Placement for PCB Design 32 Espressif Systems 6 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Contents 11 Product Handling 33 11.1 Storage Conditions 33 11.2 Electrostatic Discharge (ESD) 33 11.3 Soldering Profiles 33 11.3.1 Reflow Profile 33 11.3.2 Wave Profile 34 11.4 Ultrasonic Vibration 34 Datasheet Versioning 35 Related Documentation and Resources 36 Revision History 37 Espressif Systems 7 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 List of Tables List of Tables 1-1 ESP32-S2-SOLO-2 (ANT) Series Comparison 4 1-2 ESP32-S2-SOLO-2U (CONN) Series Comparison 1 4 3-1 Pin Definitions 12 4-1 Default Configuration of Strapping Pins 14 4-2 Description of Timing Parameters for the Strapping Pins 15 4-3 Chip Boot Mode Control 15 4-4 VDD_SPI Voltage Control 16 4-5 UART ROM Message Printing Control 16 4-6 Description of Timing Parameters for Power-up and Reset 17 5-1 Absolute Maximum Ratings 18 5-2 Recommended Operating Conditions 18 5-3 DC Characteristics (3.3 V, 25 °C) 18 5-4 RF Current Consumption in Active Mode 19 5-5 Current Consumption in Modem-sleep Mode 20 5-6 Current Consumption in Low-Power Modes 20 5-7 Flash Specifications 20 5-8 PSRAM Specifications 21 6-1 Wi-Fi RF Standards 22 6-2 TX Power with Spectral Mask and EVM Meeting 802.11 Standards 22 6-3 TX EVM Test 23 6-4 RX Sensitivity 23 6-5 Maximum RX Level 24 6-6 RX Adjacent Channel Rejection 24 Espressif Systems 8 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 List of Figures List of Figures 1-1 ESP32-S2 Module Variant Nomenclature 3 2-1 ESP32-S2-SOLO-2 Block Diagram 10 2-2 ESP32-S2-SOLO-2U Block Diagram 10 3-1 Pin Layout (Top View) 11 4-1 Visualization of Timing Parameters for the Strapping Pins 15 4-2 Visualization of Timing Parameters for Power-up and Reset 17 7-1 ESP32-S2-SOLO-2 Schematics 25 7-2 ESP32-S2-SOLO-2U Schematics 26 8-1 Peripheral Schematics 27 9-1 ESP32-S2-SOLO-2 Physical Dimensions 28 9-2 ESP32-S2-SOLO-2U Physical Dimensions 28 9-3 Dimensions of External Antenna Connector 29 10-1 ESP32-S2-SOLO-2 Recommended PCB Land Pattern 31 10-2 ESP32-S2-SOLO-2U Recommended PCB Land Pattern 32 11-1 Reflow Profile 33 11-2 Wave Soldering Profile 34 Espressif Systems 9 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 2 Block Diagram 2 Block Diagram ESP32-S2 ESP32-S2R2 RF Matching 40 MHz Crystal 3V3 ESP32-S2-SOLO-2U EN GPIOs Antenna ESP32-S2 ESP32-S2R2 RF Matching 40 MHz Crystal 3V3 ESP32-S2-SOLO-2 EN GPIOs Antenna SPI Flash SPICS0 SPICLK SPID SPIQ SPIHD SPIWP VDD_SPI SPI Flash SPICS0 SPICLK SPID SPIQ SPIHD SPIWP VDD_SPI PSRAM(opt.) (QSPI) PSRAM(opt.) (QSPI) Figure 2-1. ESP32-S2-SOLO-2 Block Diagram ESP32-S2 ESP32-S2R2 RF Matching 40 MHz Crystal 3V3 ESP32-S2-SOLO-2U EN GPIOs Antenna ESP32-S2 ESP32-S2R2 RF Matching 40 MHz Crystal 3V3 ESP32-S2-SOLO-2 EN GPIOs Antenna SPI Flash SPICS0 SPICLK SPID SPIQ SPIHD SPIWP VDD_SPI SPI Flash SPICS0 SPICLK SPID SPIQ SPIHD SPIWP VDD_SPI PSRAM(opt.) (QSPI) PSRAM(opt.) (QSPI) Figure 2-2. ESP32-S2-SOLO-2U Block Diagram Note: For the pin mapping between the chip and the in-package flash/PSRAM, please refer to ESP32-S2 Series Datasheet > Table Pin Mapping Between Chip and In-package Flash/PSRAM. Espressif Systems 10 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 3 Pin Definitions 3 Pin Definitions 3.1 Pin Layout The pin diagram below shows the approximate location of pins on the module. For the actual diagram drawn to scale, please refer to Figure 9.1 Module Dimensions. A GND 3V3 EN IO4 IO5 IO6 IO7 IO20 40 39 38 37 36 35 34 33 32 31 30 29 28 27 GND IO1 IO2 TXD0 RXD0 IO42 IO41 IO40 IO39 IO38 IO37 IO36 IO35 IO0 41 GND Keepout Zone GND GND GND GND GND GNDGNDGND 18 19 20 IO10 IO11 IO12 21 22 23 IO13 IO14 IO21 15 16 17 IO3 IO46 IO9 24 25 26 IO33 IO34 IO45 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IO15 IO16 IO17 IO18 IO8 IO19 Figure 3-1. Pin Layout (Top View) Note A: The zone marked with dotted lines is the antenna keepout zone. The pin diagram is applicable to ESP32-S2-SOLO-2 and ESP32-S2-SOLO-2U, but the latter has no antenna keepout zone. To learn more about the keepout zone for module’s antenna on the base board, please refer to ESP32-S2 Hardware Design Guidelines > Section General Principles of PCB Layout for Modules. 3.2 Pin Description The module has 41 pins. See pin definitions in Table 3-1 Pin Definitions. For peripheral pin configurations, please refer to ESP32-S2 Series Datasheet > Section Peripheral Pin Configurations. Espressif Systems 11 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 3 Pin Definitions Table 3-1. Pin Definitions Name No. Type 1 Function GND 1 P Ground 3V3 2 P Power supply EN 3 I High: on, enables the chip. Low: off, the chip powers off. Note: Do not leave the EN pin floating. IO4 4 I/O/T RTC_GPIO4, GPIO4, TOUCH4, ADC1_CH3 IO5 5 I/O/T RTC_GPIO5, GPIO5, TOUCH5, ADC1_CH4 IO6 6 I/O/T RTC_GPIO6, GPIO6, TOUCH6, ADC1_CH5 IO7 7 I/O/T RTC_GPIO7, GPIO7, TOUCH7, ADC1_CH6 IO15 8 I/O/T RTC_GPIO15, GPIO15, U0RTS, ADC2_CH4, XTAL_32K_P IO16 9 I/O/T RTC_GPIO16, GPIO16, U0CTS, ADC2_CH5, XTAL_32K_N IO17 10 I/O/T RTC_GPIO17, GPIO17, U1TXD, ADC2_CH6, DAC_1 IO18 11 I/O/T RTC_GPIO18, GPIO18, U1RXD, ADC2_CH7, DAC_2, CLK_OUT3 IO8 12 I/O/T RTC_GPIO8, GPIO8, TOUCH8, ADC1_CH7 IO19 13 I/O/T RTC_GPIO19, GPIO19, U1RTS, ADC2_CH8, CLK_OUT2, USB_D- IO20 14 I/O/T RTC_GPIO20, GPIO20, U1CTS, ADC2_CH9, CLK_OUT1, USB_D+ IO3 15 I/O/T RTC_GPIO3, GPIO3, TOUCH3, ADC1_CH2 IO46 16 I GPIO46 IO9 17 I/O/T RTC_GPIO9, GPIO9, TOUCH9, ADC1_CH8, FSPIHD IO10 18 I/O/T RTC_GPIO10, GPIO10, TOUCH10, ADC1_CH9, FSPICS0, FSPIIO4 IO11 19 I/O/T RTC_GPIO11, GPIO11, TOUCH11, ADC2_CH0, FSPID, FSPIIO5 IO12 20 I/O/T RTC_GPIO12, GPIO12, TOUCH12, ADC2_CH1, FSPICLK, FSPIIO6 IO13 21 I/O/T RTC_GPIO13, GPIO13, TOUCH13, ADC2_CH2, FSPIQ, FSPIIO7 IO14 22 I/O/T RTC_GPIO14, GPIO14, TOUCH14, ADC2_CH3, FSPIWP, FSPIDQS IO21 23 I/O/T RTC_GPIO21, GPIO21 IO33 24 I/O/T SPIIO4, GPIO33, FSPIHD IO34 25 I/O/T SPIIO5, GPIO34, FSPICS0 IO45 26 I/O/T GPIO45 IO0 27 I/O/T RTC_GPIO0, GPIO0 IO35 28 I/O/T SPIIO6, GPIO35, FSPID IO36 29 I/O/T SPIIO7, GPIO36, FSPICLK IO37 30 I/O/T SPIDQS, GPIO37, FSPIQ IO38 31 I/O/T GPIO38, FSPIWP IO39 32 I/O/T MTCK, GPIO39, CLK_OUT3 IO40 33 I/O/T MTDO, GPIO40, CLK_OUT2 IO41 34 I/O/T MTDI, GPIO41, CLK_OUT1 IO42 35 I/O/T MTMS, GPIO42 RXD0 36 I/O/T U0RXD, GPIO44, CLK_OUT2 TXD0 37 I/O/T U0TXD, GPIO43, CLK_OUT1 IO2 38 I/O/T RTC_GPIO2, GPIO2, TOUCH2, ADC1_CH1 IO1 39 I/O/T RTC_GPIO1, GPIO1, TOUCH1, ADC1_CH0 Cont’d on next page Espressif Systems 12 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 3 Pin Definitions Table 3-1 – cont’d from previous page Name No. Type 1 Function GND 40 P Ground EPAD 41 P Ground 1 P: power supply; I: input; O: output; T: high impedance. Espressif Systems 13 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 4 Boot Configurations 4 Boot Configurations Note: The content below is excerpted from ESP32-S2 Series Datasheet > Section Boot Configurations. For the strapping pin mapping between the chip and modules, please refer to Chapter 7 Module Schematics. The chip allows for configuring the following boot parameters through strapping pins and eFuse parameters at power-up or a hardware reset, without microcontroller interaction. • Chip boot mode – Strapping pins: GPIO0 and GPIO46 • VDD_SPI voltage – Strapping pin: GPIO45 – eFuse parameters: EFUSE_VDD_SPI_FORCE and EFUSE_VDD_SPI_TIEH • ROM message printing – Strapping pin: GPIO46 – eFuse parameters: EFUSE_UART_PRINT_CONTROL and EFUSE_UART_PRINT_CHANNEL The default values of all the above eFuse parameters are 0, which means that they are not burnt. Given that eFuse is one-time programmable, once programmed to 1, it can never be reverted to 0. For how to program eFuse parameters, please refer to ESP32-S2 Technical Reference Manual > Chapter eFuse Controller. The default values of the strapping pins, namely the logic levels, are determined by pins’ internal weak pull-up/pull-down resistors at reset if the pins are not connected to any circuit, or connected to an external high-impedance circuit. Table 4-1. Default Configuration of Strapping Pins Strapping Pin Default Configuration Bit Value GPIO0 Weak pull-up 1 GPIO45 Weak pull-down 0 GPIO46 Weak pull-down 0 To change the bit values, the strapping pins should be connected to external pull-down/pull-up resistances. If the ESP32-S2 is used as a device by a host MCU, the strapping pin voltage levels can also be controlled by the host MCU. All strapping pins have latches. At system reset, the latches sample the bit values of their respective strapping pins and store them until the chip is powered down or shut down. The states of latches cannot be changed in any other way. It makes the strapping pin values available during the entire chip operation, and the pins are freed up to be used as regular IO pins after reset. The timing of signals connected to the strapping pins should adhere to the setup time and hold time specifications in Table 4-2 and Figure 4-1. Espressif Systems 14 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 4 Boot Configurations Table 4-2. Description of Timing Parameters for the Strapping Pins Parameter Description Min (ms) t SU Setup time is the time reserved for the power rails to stabilize before the CHIP_PU pin is pulled high to activate the chip. 0 t H Hold time is the time reserved for the chip to read the strapping pin values after CHIP_PU is already high and before these pins start operating as regular IO pins. 3 Strapping pin V IH_nRST V IH t SU t H CHIP_PU Figure 4-1. Visualization of Timing Parameters for the Strapping Pins 4.1 Chip Boot Mode Control GPIO0 and GPIO46 control the boot mode after the reset is released. See Table 4-3 Chip Boot Mode Control. Table 4-3. Chip Boot Mode Control Boot Mode GPIO0 GPIO46 SPI boot mode 1 Any value Joint download boot mode 2 0 0 1 Bold marks the default value and configuration. 2 Joint Download Boot mode supports the following download methods: • USB-OTG Download Boot • UART Download Boot • SPI Download Boot 4.2 VDD_SPI Voltage Control Depending on the value of EFUSE_VDD_SPI_FORCE, the voltage can be controlled in two ways. Espressif Systems 15 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 4 Boot Configurations Table 4-4. VDD_SPI Voltage Control VDD_SPI power source 2 Voltage EFUSE_VDD_SPI_FORCE GPIO45 EFUSE_VDD_SPI_TIEH VDD3P3_RTC via R SP I 3.3 V 0 0 Ignored 1 Ignored 1 Flash Voltage Regulator 1.8 V 0 1 Ignored 1 Ignored 0 1 Bold marks the default value and configuration. 2 See ESP32-S2 Series Datasheet > Section Power Scheme . 4.3 ROM Messages Printing Control During the boot process, the messages by the ROM code can be printed to: • (Default) UART0 • UART1 EFUSE_UART_PRINT_CONTROL and GPIO46 control ROM messages printing to UART as shown in Table 4-5 UART ROM Message Printing Control. EFUSE_UART_PRINT_CHANNEL controls if the ROM messages will be printed to UART0 or UART1. • 0: UART0 • 1: UART1 Table 4-5. UART ROM Message Printing Control UART ROM Code Printing EFUSE_UART_PRINT_CONTROL GPIO46 Enabled 0 Ignored 1 0 2 1 Disabled 1 1 2 0 3 Ignored 1 Bold marks the default value and configuration. 4.4 Chip Power-up and Reset Once the power is supplied to the chip, its power rails need a short time to stabilize. After that, CHIP_PU – the pin used for power-up and reset – is pulled high to activate the chip. For information on CHIP_PU as well as power-up and reset timing, see Figure 4-2 and Table 4-6. Espressif Systems 16 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 4 Boot Configurations V IL_nRST t ST BL t RST 2.8 V VDDA, VDD3P3, VDD3P3_RTC, VDD3P3_RTC_IO, VDD3P3_CPU CHIP_PU Figure 4-2. Visualization of Timing Parameters for Power-up and Reset Table 4-6. Description of Timing Parameters for Power-up and Reset Parameter Description Min (µs) t ST BL Time reserved for the power rails of VDDA, VDD3P3, VDD3P3_RTC, VDD3P3_RTC_IO, and VDD3P3_CPU to stabilize before the CHIP_PU pin is pulled high to activate the chip 50 t RST Time reserved for CHIP_PU to stay below V IL_nRST to reset the chip (see Table 5-3) 50 Espressif Systems 17 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 5 Electrical Characteristics 5 Electrical Characteristics 5.1 Absolute Maximum Ratings Stresses above those listed in Table 5-1 Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under Table 5-2 Recommended Operating Conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Table 5-1. Absolute Maximum Ratings Symbol Parameter Min Max Unit VDD33 Power supply voltage –0.3 3.6 V T ST OR E Storage temperature –40 105 °C 5.2 Recommended Operating Conditions Table 5-2. Recommended Operating Conditions Symbol Parameter Min Typ Max Unit VDD33 Power supply voltage 3.0 3.3 3.6 V I V DD Current delivered by external power supply 0.5 — — A T A Operating ambient temperature 85 °C version –40 — 85 °C 105 °C version 105 5.3 DC Characteristics (3.3 V, 25 °C) Table 5-3. DC Characteristics (3.3 V, 25 °C) Parameter Description Min Typ Max Unit C IN Pin capacitance — 2 — pF V IH High-level input voltage 0.75 × VDD 1 — VDD 1 + 0.3 V V IL Low-level input voltage –0.3 — 0.25 × VDD 1 V I IH High-level input current — — 50 nA I IL Low-level input current — — 50 nA V OH 2 High-level output voltage 0.8 × VDD 1 — — V V OL 2 Low-level output voltage — — 0.1 × VDD 1 V I OH High-level source current (VDD 1 = 3.3 V, V OH >= 2.64 V, PAD_DRIVER = 3) — 40 — mA I OL Low-level sink current (VDD 1 = 3.3 V, V OL = 0.495 V, PAD_DRIVER = 3) — 28 — mA R P U Internal weak pull-up resistor — 45 — kΩ R P D Internal weak pull-down resistor — 45 — kΩ Espressif Systems 18 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 5 Electrical Characteristics V IH_nRST Chip reset release voltage (CHIP_PU voltage is within the specified range) 0.75 × VDD 1 — VDD 1 + 0.3 V V IL_nRST Chip reset voltage (CHIP_PU voltage is within the specified range) –0.3 — 0.25 × VDD 1 V 1 VDD – voltage from a power pin of a respective power domain. 2 V OH and V OL are measured using high-impedance load. 5.4 Current Consumption Characteristics Owing to the use of advanced power-management technologies, the module can switch between different power modes. For details on different power modes, please refer to Section RTC and Low-Power Management in ESP32-S2 Series Datasheet. 5.4.1 Current Consumption in Active Mode Table 5-4. RF Current Consumption in Active Mode Work mode Description Peak (mA) Active (RF working) TX 802.11b, 20 MHz, 1 Mbps, @19.5 dBm 320 802.11g, 20 MHz, 54 Mbps, @17.5 dBm 273 802.11n, 20 MHz, MCS7, @16.5 dBm 265 802.11n, 40 MHz, MCS7, @16.5 dBm 274 RX 802.11b/g/n, 20 MHz 77 802.11n, 40 MHz 81 1 The current consumption measurements are taken with a 3.3 V supply at 25 °C of ambient temperature at the RF port. All transmitters’ measurements are based on 100% duty cycle. 2 The current consumption figures in RX mode are for cases where the peripherals are disabled and the CPU idle. Note: The content below is excerpted from Section Power Consumption in Other Modes in ESP32-S2 Series Datasheet. 5.4.2 Current Consumption in Other Modes The measurements below are applicable to ESP32-S2, ESP32-S2FH2, and ESP32-S2FH4. Since ESP32-S2FN4R2 and ESP32-S2R2 come with in-package PSRAM, their current consumption might be higher. Espressif Systems 19 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 5 Electrical Characteristics Table 5-5. Current Consumption in Modem-sleep Mode Typ Mode CPU Frequency (MHz) Description All Peripherals Clocks Disabled (mA) All Peripherals Clocks Enabled (mA) 1 Modem-sleep 2,3 240 CPU is idle 20.0 28.0 CPU is running 23.0 32.0 160 CPU is idle 14.0 21.0 CPU is running 16.0 24.0 80 CPU is idle 10.5 18.4 CPU is running 12.0 20.0 1 In practice, the current consumption might be different depending on which peripherals are enabled. 2 In Modem-sleep mode, Wi-Fi is clock gated. 3 In Modem-sleep mode, the consumption might be higher when accessing flash. For a flash rated at 80 Mbit/s, in SPI 2-line mode the consumption is 10 mA. Table 5-6. Current Consumption in Low-Power Modes Work mode Description Typ (µA) Light-sleep 1 VDD_SPI and Wi-Fi are powered down, and all GPIOs are high-impedance 750 Deep-sleep The ULP co-processor is powered on 2 ULP-FSM 170 ULP-RISC-V 190 ULP sensor-monitored pattern 3 22 RTC timer + RTC memory 25 RTC timer only 20 Power off CHIP_PU is set to low level, the chip is powered off 1 1 In Light-sleep mode, with all related SPI pins pulled up, the current consumption of the embedded PSRAM is 140 µA. Chip variants with in-package PSRAM include ESP32-S2FN4R2 and ESP32-S2R2. 2 During Deep-sleep, when the ULP co-processor is powered on, peripherals such as GPIO and I2C are able to operate. 3 The “ULP sensor-monitored pattern” refers to the mode where the ULP coprocessor or the sensor works periodically. When touch sensors work with a duty cycle of 1%, the typical current consumption is 22 µA. 5.5 Memory Specifications The data below is sourced from the memory vendor datasheet. These values are guaranteed through design and/or characterization but are not fully tested in production. Devices are shipped with the memory erased. Table 5-7. Flash Specifications Parameter Description Min Typ Max Unit VCC Power supply voltage (1.8 V) 1.65 1.80 2.00 V Cont’d on next page Espressif Systems 20 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 5 Electrical Characteristics Table 5-7 – cont’d from previous page Parameter Description Min Typ Max Unit Power supply voltage (3.3 V) 2.7 3.3 3.6 V F C Maximum clock frequency 80 — — MHz — Program/erase cycles 100,000 — — cycles T RET Data retention time 20 — — years T P P Page program time — 0.8 5 ms T SE Sector erase time (4 KB) — 70 500 ms T BE1 Block erase time (32 KB) — 0.2 2 s T BE2 Block erase time (64 KB) — 0.3 3 s T CE Chip erase time (16 Mb) — 7 20 s Chip erase time (32 Mb) — 20 60 s Chip erase time (64 Mb) — 25 100 s Chip erase time (128 Mb) — 60 200 s Chip erase time (256 Mb) — 70 300 s Table 5-8. PSRAM Specifications Parameter Description Min Typ Max Unit VCC Power supply voltage (1.8 V) 1.62 1.80 1.98 V Power supply voltage (3.3 V) 2.7 3.3 3.6 V F C Maximum clock frequency 80 — — MHz Espressif Systems 21 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 6 RF Characteristics 6 RF Characteristics This section contains tables with RF characteristics of the Espressif product. The RF data is measured at the antenna port, where RF cable is connected, including the front-end loss. The external antennas used for the tests on the modules with external antenna connectors have an impedance of 50 Ω. Devices should operate in the center frequency range allocated by regional regulatory authorities. The target center frequency range and the target transmit power are configurable by software. See ESP RF Test Tool and Test Guide for instructions. Unless otherwise stated, the RF tests are conducted with a 3.3 V (±5%) supply at 25 ºC ambient temperature. 6.1 Wi-Fi Radio 6.1.1 Wi-Fi RF Standards Table 6-1. Wi-Fi RF Standards Name Description Center frequency range of operating channel 1 2412 ~ 2484 MHz Wi-Fi wireless standard IEEE 802.11b/g/n Data rate 20 MHz 802.11b: 1, 2, 5.5 and 11 Mbps 802.11g: 6, 9, 12, 18, 24, 36, 48, 54 Mbps 802.11n: MCS0-7, 72.2 Mbps (Max) 40 MHz 802.11n: MCS0-7, 150 Mbps (Max) Antenna type PCB antenna, external antenna connector 1 Device should operate in the center frequency range allocated by regional regulatory authorities. Target center frequency range is configurable by software. See ESP RF Test Tool and Test Guide for instructions. 2 For the modules that use external antenna connectors, the output impedance is 50 Ω. For other modules without external antenna connectors, the output impedance is irrelevant. 6.1.2 Wi-Fi RF Transmitter (TX) Specifications Target TX power is configurable based on device or certification requirements. The default characteristics are provided in Table 6-2. Table 6-2. TX Power with Spectral Mask and EVM Meeting 802.11 Standards Min Typ Max Rate (dBm) (dBm) (dBm) 802.11b, 1 Mbps — 19.5 — 802.11b, 11 Mbps — 19.5 — 802.11g, 6 Mbps — 17.5 — Cont’d on next page Espressif Systems 22 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 6 RF Characteristics Table 6-2 – cont’d from previous page Min Typ Max Rate (dBm) (dBm) (dBm) 802.11g, 54 Mbps — 17.5 — 802.11n, HT20, MCS0 — 17.5 — 802.11n, HT20, MCS7 — 16.5 — 802.11n, HT40, MCS0 — 17.5 — 802.11n, HT40, MCS7 — 16.5 — Table 6-3. TX EVM Test Min Typ SL 1 Rate (dB) (dB) (dB) 802.11b, 1 Mbps, @19.5 dBm — –25.0 –10 802.11b, 11 Mbps, @19.5 dBm — –25.0 –10 802.11g, 6 Mbps, @17.5 dBm — –25.0 –5 802.11g, 54 Mbps, @17.5 dBm — –28.0 –25 802.11n, HT20, MCS0, @17.5 dBm — –27.0 –5 802.11n, HT20, MCS7, @16.5 dBm — –30.5 –27 802.11n, HT40, MCS0, @17.5 dBm — –27.0 –5 802.11n, HT40, MCS7, @16.5 dBm — –30.0 –27 1 SL stands for standard limit value. 6.1.3 Wi-Fi RF Receiver (RX) Specifications Table 6-4. RX Sensitivity Min Typ Max Rate (dBm) (dBm) (dBm) 802.11b, 1 Mbps — –97.0 — 802.11b, 2 Mbps — –94.5 — 802.11b, 5.5 Mbps — –92.0 — 802.11b, 11 Mbps — –88.5 — 802.11g, 6 Mbps — –92.5 — 802.11g, 9 Mbps — –91.0 — 802.11g, 12 Mbps — –89.5 — 802.11g, 18 Mbps — –87.5 — 802.11g, 24 Mbps — –84.5 — 802.11g, 36 Mbps — –80.5 — 802.11g, 48 Mbps — –76.5 — 802.11g, 54 Mbps — –75.0 — 802.11n, HT20, MCS0 — –92.0 — 802.11n, HT20, MCS1 — –89.0 — 802.11n, HT20, MCS2 — –86.5 — Cont’d on next page Espressif Systems 23 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 6 RF Characteristics Table 6-4 – cont’d from previous page Min Typ Max Rate (dBm) (dBm) (dBm) 802.11n, HT20, MCS3 — –83.5 — 802.11n, HT20, MCS4 — –79.5 — 802.11n, HT20, MCS5 — –75.5 — 802.11n, HT20, MCS6 — –74.0 — 802.11n, HT20, MCS7 — –72.5 — 802.11n, HT40, MCS0 — –89.0 — 802.11n, HT40, MCS1 — –86.5 — 802.11n, HT40, MCS2 — –84.0 — 802.11n, HT40, MCS3 — –80.0 — 802.11n, HT40, MCS4 — –76.5 — 802.11n, HT40, MCS5 — –72.5 — 802.11n, HT40, MCS6 — –71.0 — 802.11n, HT40, MCS7 — –69.5 — Table 6-5. Maximum RX Level Min Typ Max Rate (dBm) (dBm) (dBm) 802.11b, 1 Mbps — 5 — 802.11b, 11 Mbps — 5 — 802.11g, 6 Mbps — 5 — 802.11g, 54 Mbps — 0 — 802.11n, HT20, MCS0 — 5 — 802.11n, HT20, MCS7 — 0 — 802.11n, HT40, MCS0 — 5 — 802.11n, HT40, MCS7 — 0 — Table 6-6. RX Adjacent Channel Rejection Min Typ Max Rate (dB) (dB) (dB) 802.11b, 1 Mbps — 35 — 802.11b, 11 Mbps — 35 — 802.11g, 6 Mbps — 31 — 802.11g, 54 Mbps — 14 — 802.11n, HT20, MCS0 — 31 — 802.11n, HT20, MCS7 — 13 — 802.11n, HT40, MCS0 — 19 — 802.11n, HT40, MCS7 — 8 — Espressif Systems 24 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 7 Module Schematics 7 Module Schematics This is the reference design of the module. 5 5 4 4 3 3 2 2 1 1 D D C C B B A A The values of L3, C17, C11, L2 and C12 vary with the actual PCB board. The values of C1 and C4 vary with the selection of the crystal. The value of R4 varies with the actual PCB board. ESP32-S2-SOLO-2(pin-out) ESP32-S2 ESP32-S2R2 NC: No component. SPICLK SPICS0 SPIHD SPID SPIWP SPIQ GPIO0 GPIO1 GPIO2 GPIO4 GPIO9 GPIO10 GPIO11 GPIO12 GPIO13 GPIO14 GPIO15 GPIO16 GPIO17 GPIO18 GPIO19 GPIO20 GPIO21 GPIO33 GPIO34 GPIO35 GPIO36 GPIO37 GPIO38 SPICS0 LNA_INRF_ANT GPIO39 GPIO40 GPIO41 GPIO42 U0RXD GPIO46 CHIP_PU GPIO45 U0TXD SPICLK GPIO8 GPIO5 GPIO6 GPIO7 CHIP_PU GPIO4 GPIO5 GPIO6 GPIO7 GPIO15 GPIO16 GPIO17 GPIO18 GPIO3 GPIO46 GPIO9 GPIO10 GPIO11 GPIO12 GPIO13 GPIO14 GPIO21 GPIO33 GPIO34 GPIO45 GPIO0 GPIO35 GPIO36 GPIO37 GPIO38 GPIO39 GPIO40 GPIO41 GPIO42 U0RXD U0TXD GPIO2 GPIO1 GPIO3 GPIO19 GPIO20 GPIO8 SPIHD SPIWP SPIQ SPID VDD_SPI GND GND GND GND VDD33 GND GND GND GNDGND GND GND VDD33 VDD33 GND GNDGND VDD33 GND GNDGND VDD33 GND VDD33 GND GND GND VDD33 VDD_SPI GNDVDD33 GND GND GND VDD33 R15 0 C11 TBD C13 0.1uF C12 TBD L3 TBD C4 TBD R3 499 R14 0 C14 1uF R8 10K(NC) R13 0 C9 100pF U1 VDDA 1 LNA_IN 2 VDD3P3 3 VDD3P3 4 GPIO0 5 GPIO1 6 GPIO2 7 GPIO3 8 GPIO4 9 GPIO5 10 GPIO6 11 GPIO7 12 GPIO10 15 GPIO11 16 GPIO12 17 GPIO13 18 GPIO14 19 XTAL_32K_P 21 VDD3P3_RTC 20 XTAL_32K_N 22 DAC_1 23 DAC_2 24 GPIO19 25 GPIO20 26 VDD_SPI 30 SPICS1 29 SPIWP 32 SPICS0 33 SPIQ 35 SPID 36 SPICLK 34 GPIO33 37 GND 57 GPIO34 38 GPIO35 39 MTCK 43 GPIO46 55 VDDA 51 XTAL_N 52 XTAL_P 53 MTMS 47 MTDO 44 U0TXD 48 VDD3P3_CPU 45 CHIP_PU 56 VDDA 54 MTDI 46 GPIO8 13 GPIO9 14 VDD3P3_RTC_IO 27 GPIO21 28 SPIHD 31 GPIO36 40 GPIO37 41 GPIO38 42 U0RXD 49 GPIO45 50 L1 2.0nH C6 10uF C2 100pF Y1 40MHz(±10ppm) XIN 1 GND 2 XOUT 3 GND 4 C10 0.1uF U2 FLASH-3V3 VDD 8 GND 4 /CS 1 CLK 6 /HOLD 7 /WP 3 DO 2 DI 5 R1 10K(NC) C7 1uF L2 TBD U3 ESP32-S2-SOLO-2 GND 1 3V3 2 EN 3 IO4 4 IO5 5 IO6 6 IO7 7 IO15 8 IO16 9 IO17 10 IO18 11 IO19 13 IO20 14 IO8 12 GND 40 IO1 39 IO2 38 TXD0 37 RXD0 36 IO42 35 IO41 34 IO40 33 IO39 32 IO38 31 IO37 30 IO36 29 IO35 28 IO0 27 IO46 16 IO9 17 IO10 18 IO11 19 IO12 20 IO13 21 IO14 22 IO21 23 IO33 24 IO34 25 IO3 15 IO45 26 EPAD 41 ANT1 PCB_ANT 1 2 C1 TBD R16 0 C17 TBD R10 0 D1 ESD C16 0.1uF C3 1uF C15 0.1uF R4 0 C5 0.1uF C8 0.1uF Figure 7-1. ESP32-S2-SOLO-2 Schematics Espressif Systems 25 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 7 Module Schematics 5 5 4 4 3 3 2 2 1 1 D D C C B B A A The values of C11, L2 and C12 vary with the actual PCB board. The values of C1 and C4 vary with the selection of the crystal. The value of R4 varies with the actual PCB board. ESP32-S2-SOLO-2U(pin-out) ESP32-S2 ESP32-S2R2 NC: No component. SPICLK SPICS0 SPIHD SPID SPIWP SPIQ GPIO0 GPIO1 GPIO2 GPIO4 GPIO9 GPIO10 GPIO11 GPIO12 GPIO13 GPIO14 GPIO15 GPIO16 GPIO17 GPIO18 GPIO19 GPIO20 GPIO21 GPIO33 GPIO34 GPIO35 GPIO36 GPIO37 GPIO38 SPICS0 LNA_INRF_ANT GPIO39 GPIO40 GPIO41 GPIO42 U0RXD GPIO46 CHIP_PU GPIO45 U0TXD SPICLK GPIO8 GPIO5 GPIO6 GPIO7 CHIP_PU GPIO4 GPIO5 GPIO6 GPIO7 GPIO15 GPIO16 GPIO17 GPIO18 GPIO3 GPIO46 GPIO9 GPIO10 GPIO11 GPIO12 GPIO13 GPIO14 GPIO21 GPIO33 GPIO34 GPIO45 GPIO0 GPIO35 GPIO36 GPIO37 GPIO38 GPIO39 GPIO40 GPIO41 GPIO42 U0RXD U0TXD GPIO2 GPIO1 GPIO3 GPIO19 GPIO20 GPIO8 SPIHD SPIWP SPIQ SPID VDD_SPI GND GND GND GND VDD33 GND GND GND GNDGND GND GND VDD33 VDD33 GND GNDGND VDD33 GND GNDGND VDD33 GND VDD33 GND GND GND VDD33 VDD_SPI GNDVDD33 GND GND VDD33 C11 TBD R15 0 C12 TBD C13 0.1uF C4 TBD R3 499 R13 0 R8 10K(NC) C14 1uF R14 0 U1 VDDA 1 LNA_IN 2 VDD3P3 3 VDD3P3 4 GPIO0 5 GPIO1 6 GPIO2 7 GPIO3 8 GPIO4 9 GPIO5 10 GPIO6 11 GPIO7 12 GPIO10 15 GPIO11 16 GPIO12 17 GPIO13 18 GPIO14 19 XTAL_32K_P 21 VDD3P3_RTC 20 XTAL_32K_N 22 DAC_1 23 DAC_2 24 GPIO19 25 GPIO20 26 VDD_SPI 30 SPICS1 29 SPIWP 32 SPICS0 33 SPIQ 35 SPID 36 SPICLK 34 GPIO33 37 GND 57 GPIO34 38 GPIO35 39 MTCK 43 GPIO46 55 VDDA 51 XTAL_N 52 XTAL_P 53 MTMS 47 MTDO 44 U0TXD 48 VDD3P3_CPU 45 CHIP_PU 56 VDDA 54 MTDI 46 GPIO8 13 GPIO9 14 VDD3P3_RTC_IO 27 GPIO21 28 SPIHD 31 GPIO36 40 GPIO37 41 GPIO38 42 U0RXD 49 GPIO45 50 C9 100pF C6 10uF D1 ESD L1 2.4nH R1 10K(NC) U2 FLASH-3V3 VDD 8 GND 4 /CS 1 CLK 6 /HOLD 7 /WP 3 DO 2 DI 5 C10 0.1uF Y1 40MHz(±10ppm) XIN 1 GND 2 XOUT 3 GND 4 C2 100pF L2 TBD C7 1uF C1 TBD ANT1 CONN 1 2 3 U3 ESP32-S2-SOLO-2U GND 1 3V3 2 EN 3 IO4 4 IO5 5 IO6 6 IO7 7 IO15 8 IO16 9 IO17 10 IO18 11 IO19 13 IO20 14 IO8 12 GND 40 IO1 39 IO2 38 TXD0 37 RXD0 36 IO42 35 IO41 34 IO40 33 IO39 32 IO38 31 IO37 30 IO36 29 IO35 28 IO0 27 IO46 16 IO9 17 IO10 18 IO11 19 IO12 20 IO13 21 IO14 22 IO21 23 IO33 24 IO34 25 IO3 15 IO45 26 EPAD 41 R10 0 R16 0 C3 1uF C16 0.1uF C15 0.1uF R4 0 C8 0.1uF C5 0.1uF Figure 7-2. ESP32-S2-SOLO-2U Schematics Espressif Systems 26 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 8 Peripheral Schematics 8 Peripheral Schematics This is the typical application circuit of the module connected with peripheral components (for example, power supply, antenna, reset button, JTAG interface, and UART interface). 5 5 4 4 3 3 2 2 1 1 D D C C B B A A NC: No component. X1: ESR = Max. 70 KΩ EN IO42 TMS IO41 TDI IO37 IO36 IO38 IO40 TDO IO39 TCK TXD0 RXD0 IO35 IO34 IO33 IO12 IO13 IO3 IO6 IO7 IO9 IO10 IO11 IO15 IO16 IO14 IO21 IO17 IO18 USB_D- USB_D+ IO1 IO2 IO45 IO4 IO5 IO0 EN IO19 IO20 IO46 IO8 GND GND GND VDD33 GND GND GND GND GND VDD33 GNDGND GND GND C4 12pF(NC) SW1 JP4 Boot Option 1 1 2 2 C3 0.1uF U1 ESP32-S2-SOLO-2/ESP32-S2-SOLO-2U GND 1 3V3 2 EN 3 IO4 4 IO5 5 IO6 6 IO7 7 IO15 8 IO16 9 IO17 10 IO18 11 IO19 13 IO20 14 IO8 12 GND 40 IO1 39 IO2 38 TXD0 37 RXD0 36 IO42 35 IO41 34 IO40 33 IO39 32 IO38 31 IO37 30 IO36 29 IO35 28 IO0 27 IO46 16 IO9 17 IO10 18 IO11 19 IO12 20 IO13 21 IO14 22 IO21 23 IO33 24 IO34 25 IO3 15 IO45 26 EPAD 41 R4 0 R7 0 R1 TBD X1 32.768KHz(NC) 12 R2 NC C5 TBD R5 0(NC) JP1 UART 1 1 2 2 3 3 4 4 R3 0(NC) C1 22uF C8 0.1uF R6 0 JP3 USB OTG 1 1 2 2 JP2 JTAG 1 1 2 2 3 3 4 4 C2 TBD C6 TBD C7 12pF(NC) Figure 8-1. Peripheral Schematics • Soldering the EPAD to the ground of the base board is not a must, however, it can optimize thermal performance. If you choose to solder it, please apply the correct amount of soldering paste. Too much soldering paste may increase the gap between the module and the baseboard. As a result, the adhesion between other pins and the baseboard may be poor. • To ensure that the power supply to the ESP32-S2 chip is stable during power-up, it is advised to add an RC delay circuit at the EN pin. The recommended setting for the RC delay circuit is usually R = 10 kΩ and C = 1 µF. However, specific parameters should be adjusted based on the power-up timing of the module and the power-up and reset sequence timing of the chip. For ESP32-S2’s power-up and reset sequence timing diagram, please refer to ESP32-S2 Series Datasheet > Section Power Scheme. Espressif Systems 27 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 9 Physical Dimensions 9 Physical Dimensions 9.1 Module Dimensions 1.27 40 x 0.9 17.6 40 x 0.45 1.05 1 0.8 40 x 0.85 0.5 3.7 40 x Ø0.55 25.5±0.15 1.5 16.51 40 x 0.9 3.1±0.15 Top View Side View Bottom View 18±0.15 15.8 6 0.9 Ø0.5 Unit: mm 13.97 1.27 2.015 0.9 3.7 10.29 7.5 Figure 9-1. ESP32-S2-SOLO-2 Physical Dimensions 1.5 1.27 16.51 40 x 0.9 Top View Bottom View 18±0.15 40 x 0.45 40 x 0.85 0.5 3.7 10.75 15.65 17.5 0.9 Side View 40 x 0.9 19.2±0.15 40 x Ø0.55 0.8 1.08 1.1 2.46 3 1.27 3.2±0.15 Unit: mm 13.97 2.015 13.1 7.5 10.29 0.9 3.7 Figure 9-2. ESP32-S2-SOLO-2U Physical Dimensions Note: For information about tape, reel, and product marking, please refer to ESP32-S2 Module Packaging Information. Espressif Systems 28 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 9 Physical Dimensions 9.2 Dimensions of External Antenna Connector ESP32-S2-SOLO-2U uses the first generation external antenna connector as shown in Figure 9-3 Dimensions of External Antenna Connector. This connector is compatible with the following connectors: • U.FL Series connector from Hirose • MHF I connector from I-PEX • AMC connector from Amphenol Unit: mm Figure 9-3. Dimensions of External Antenna Connector The external antenna used for ESP32-S2-SOLO-2U during certification testing is the first generation monopole Espressif Systems 29 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 9 Physical Dimensions antenna, with material code TFPD05H08750011. The module does not include an external antenna upon shipment. If needed, select a suitable external antenna based on the product’s usage environment and performance requirements. It is recommended to select an antenna that meets the following requirements: • 2.4 GHz band • 50 Ω impedance • The maximum gain does not exceed 2.33 dBi, the gain of the antenna used for certification • The connector matches the specifications shown in Figure 9-3 Dimensions of External Antenna Connector Note: If you use an external antenna of a different type or gain, additional testing, such as EMC, may be required beyond the existing antenna test reports for Espressif modules. Specific requirements depend on the certification type. Espressif Systems 30 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 10 PCB Layout Recommendations 10 PCB Layout Recommendations 10.1 PCB Land Pattern This section provides the following resources for your reference: • Figures for recommended PCB land patterns with all the dimensions needed for PCB design. See Figure 10-1 ESP32-S2-SOLO-2 Recommended PCB Land Pattern and Figure 10-2 ESP32-S2-SOLO-2U Recommended PCB Land Pattern. • Source files of recommended PCB land patterns to measure dimensions not covered in Figure 10-1 and Figure 10-2. You can view the source files for ESP32-S2-SOLO-2 and ESP32-S2-SOLO-2U with Autodesk Viewer. • 3D models of ESP32-S2-SOLO-2 and ESP32-S2-SOLO-2U. Please make sure that you download the 3D model file in .STEP format (beware that some browsers might add .txt). Antenna Area 1 40 18 25.5 1.5 3.7 0.9 15 26 40 x0.9 40 x1.5 3.7 6 7.5 0.9 1.27 0.5 Unit: mm Copper Via for thermal pad 7.49 0.5 0.5 2.015 2.015 1.27 17.5 10.29 16.51 Figure 10-1. ESP32-S2-SOLO-2 Recommended PCB Land Pattern Espressif Systems 31 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 10 PCB Layout Recommendations 1 19.2 15 18 26 1.5 40 x1.5 0.5 0.5 3.7 0.9 0.9 7.5 1.27 3.7 40 40 x0.9 0.5 Unit: mm Via for thermal pad Copper 10.29 1.27 2.015 2.015 17.5 16.51 1.19 Figure 10-2. ESP32-S2-SOLO-2U Recommended PCB Land Pattern 10.2 Module Placement for PCB Design If module-on-board design is adopted, attention should be paid while positioning the module on the base board. The interference of the base board on the module’s antenna performance should be minimized. For details about module placement for PCB design, please refer to ESP32-S2 Hardware Design Guidelines > Section General Principles of PCB Layout for Modules. Espressif Systems 32 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 11 Product Handling 11 Product Handling 11.1 Storage Conditions The products sealed in moisture barrier bags (MBB) should be stored in a non-condensing atmospheric environment of < 40 °C and 90%RH. The module is rated at the moisture sensitivity level (MSL) of 3. After unpacking, the module must be soldered within 168 hours with the factory conditions 25±5 °C and 60%RH. If the above conditions are not met, the module needs to be baked. 11.2 Electrostatic Discharge (ESD) • Human body model (HBM): ±2000 V • Charged-device model (CDM): ±500 V 11.3 Soldering Profiles 11.3.1 Reflow Profile Solder the module in a single reflow. 50 100 0 150 200 250 200 100 50 150 250 Time (s) 217 25 Preheating 150 – 200 °C 60 – 120 s Ramp-up 25 – 150 °C 60 – 90 s 1 – 3 °C/s Soldering ＞ 217 °C 60 – 90 s Peak temperature: 235 – 250 °C Peak time: 30 – 70 s Soldering time: ＞ 30 s Solder: Sn-Ag-Cu (SAC305) lead-free solder Temperature (°C) 180 230 Cooling ＜ 180 °C –5 ~ –1 °C/s Figure 11-1. Reflow Profile Espressif Systems 33 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 11 Product Handling 11.3.2 Wave Profile 50 100 0 200150 250 Temperature (°C) Time (s) 80 Peak temperature: 230 – 260 °C Component Temperature Preheating Component temperature: 90 – 120 °C PCB soak time: 2 – 5 s PCB ramp-up rate: ≤ 5 °C/s Soldering Solder point temperature: 245 ± 10 °C Cooling Exit temperature: ＜ 100 °C Solder Point Temperature 150 200 250 120 50 160 260 90 230 100 Figure 11-2. Wave Soldering Profile 11.4 Ultrasonic Vibration Avoid exposing Espressif modules to vibration from ultrasonic equipment, such as ultrasonic welders or ultrasonic cleaners. This vibration may induce resonance in the in-module crystal and lead to its malfunction or even failure. As a consequence, the module may stop working or its performance may deteriorate. Espressif Systems 34 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Datasheet Versioning Datasheet Versioning Datasheet Version Status Watermark Definition v0.1 ~ v0.5 (excluding v0.5) Draft Confidential This datasheet is under development for products in the design stage. Specifications may change without prior notice. v0.5 ~ v1.0 (excluding v1.0) Preliminary release Preliminary This datasheet is actively updated for products in the verification stage. Specifications may change before mass production, and the changes will be documentation in the datasheet’s Revision History. v1.0 and higher Official release — This datasheet is publicly released for products in mass production. Specifications are finalized, and major changes will be communicated via Product Change Notifications (PCN). Any version — Not Recommended for New Design (NRND) 1 This datasheet is updated less frequently for products not recommended for new designs. Any version — End of Life (EOL) 2 This datasheet is no longer mtained for products that have reached end of life. 1 Watermark will be added to the datasheet title page only when all the product variants covered by this datasheet are not recommended for new designs. 2 Watermark will be added to the datasheet title page only when all the product variants covered by this datasheet have reached end of life. Espressif Systems 35 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Related Documentation and Resources Related Documentation and Resources Related Documentation • ESP32-S2 Series Datasheet – Specifications of the ESP32-S2 hardware. • ESP32-S2 Technical Reference Manual – Detailed information on how to use the ESP32-S2 memory and peripherals. • ESP32-S2 Hardware Design Guidelines – Guidelines on how to integrate the ESP32-S2 into your hardware product. • ESP32-S2 Series SoC Errata – Descriptions of known errors in ESP32-S2 series of SoCs. • Certificates https://espressif.com/en/support/documents/certificates • ESP32-S2 Product/Process Change Notifications (PCN) https://espressif.com/en/support/documents/pcns?keys=ESP32-S2 • ESP32-S2 Advisories – Information on security, bugs, compatibility, component reliability. https://espressif.com/en/support/documents/advisories?keys=ESP32-S2 • Documentation Updates and Update Notification Subscription https://espressif.com/en/support/download/documents Developer Zone • ESP-IDF Programming Guide for ESP32-S2 – Extensive documentation for the ESP-IDF development framework. • ESP-IDF and other development frameworks on GitHub. https://github.com/espressif • ESP32 BBS Forum – Engineer-to-Engineer (E2E) Community for Espressif products where you can post questions, share knowledge, explore ideas, and help solve problems with fellow engineers. https://esp32.com/ • ESP-FAQ – A summary document of frequently asked questions released by Espressif. https://espressif.com/projects/esp-faq/en/latest/index.html • The ESP Journal – Best Practices, Articles, and Notes from Espressif folks. https://blog.espressif.com/ • See the tabs SDKs and Demos, Apps, Tools, AT Firmware. https://espressif.com/en/support/download/sdks-demos Products • ESP32-S2 Series SoCs – Browse through all ESP32-S2 SoCs. https://espressif.com/en/products/socs?id=ESP32-S2 • ESP32-S2 Series Modules – Browse through all ESP32-S2-based modules. https://espressif.com/en/products/modules?id=ESP32-S2 • ESP32-S2 Series DevKits – Browse through all ESP32-S2-based devkits. https://espressif.com/en/products/devkits?id=ESP32-S2 • ESP Product Selector – Find an Espressif hardware product suitable for your needs by comparing or applying filters. https://products.espressif.com/#/product-selector?language=en Contact Us • See the tabs Sales Questions, Technical Enquiries, Circuit Schematic & PCB Design Review, Get Samples (Online stores), Become Our Supplier, Comments & Suggestions. https://espressif.com/en/contact-us/sales-questions Espressif Systems 36 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Revision History Revision History Date Version Release notes 2026-03-02 v1.4 • Updated “Ordering Code” to “Part Number” 2025-11-24 v1.3 • Added Section 4.4 Chip Power-up and Reset • Added Section 5.5 Memory Specifications • Added Section 11.4 Datasheet Versioning • Upgraded document template 2025-11-07 v1.2 • In Chapter Series Comparison: – Added Figure 1-1 ESP32-S2 Module Variant Nomenclature – Removed ESP32-S2-SOLO-2-N8R2, ESP32-S2-SOLO-2-N16R2, ESP32-S2-SOLO-2U-N8,ESP32-S2-SOLO-2U-N8R2 and ESP32-S2-SOLO-2U-N16R2 – Marked ESP32-S2-SOLO-2-N8 and ESP32-S2-SOLO-2-H4 end of life • In Section 9.2 Dimensions of External Antenna Connector: Added the external antenna information for certification • In Chapter 10.1 PCB Land Pattern: added 3D models 2024-09-05 v1.1 Formatting updates 2024-05-10 v1.0 • Added information about certification and test in Section 1.1 Features 2024-04-16 v0.6 • Updated EPAD descriptions in Section 8 Peripheral Schematics • Added descriptions in Section 10.1 PCB Land Pattern • Other formatting updates 2022-09-19 v0.5 Preliminary release Espressif Systems 37 Submit Documentation Feedback ESP32-S2-SOLO-2 & SOLO-2U Datasheet v1.4 Disclaimer and Copyright Notice Information in this document, including URL references, is subject to change without notice. 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