ESP-WROOM-02U

ESP-WROOM-02D/02U Datasheet Includes: ESP-WROOM-02D ESP-WROOM-02U Version 1.2 Espressif Systems Copyright © 2018 www.espressif.com About This Guide This document provides introduction to the specifications of ESP-WROOM-02D and ESPWROOM-02U hardware. Release Notes Date Version Release notes 2017.11 V1.0 First release. 2018.03 V1.1 Updated the figure of ESP-WROOM-02U dimensions. • Updated Table 1-1 and Table 1-2; 2018.08 V1.2 • Updated module dimensions; • Added PCB pattern; • Updated document cover. Documentation Change Notification Espressif provides email notifications to keep customers updated on changes to technical documentation. Please subscribe at https://www.espressif.com/en/subscribe. Certification Download certificates for Espressif products from https://www.espressif.com/en/ certificates. Table of Contents 1. Overview ................................................................................................................................ 1 2. Pin Description ......................................................................................................................3 3. Functional Description ..........................................................................................................5 3.1. CPU ..........................................................................................................................................5 3.2. Memory .................................................................................................................................... 5 3.2.1. Internal SRAM and ROM ...........................................................................................5 3.2.2. SPI Flash .................................................................................................................... 5 3.3. Crystal Oscillator ...................................................................................................................... 6 3.4. Interface Description ................................................................................................................6 4. Electrical Characteristics ...................................................................................................... 8 4.1. Electrical Characteristics ..........................................................................................................8 4.2. Wi-Fi Radio ...............................................................................................................................8 4.3. Power Consumption ................................................................................................................. 9 4.4. Reflow Profile .........................................................................................................................10 4.5. Electrostatic Discharge ..........................................................................................................11 5. Schematics ..........................................................................................................................12 6. Peripheral Schematics ........................................................................................................14 7. Dimensions ..........................................................................................................................15 8. Recommended PCB Land Pattern ..................................................................................... 17 9. U.FL Connector Dimensions ...............................................................................................19 A. Appendix—Learning Resources .........................................................................................20 A.1. Must-Read Documents ..........................................................................................................20 A.2. Must-Have Resources ............................................................................................................21 1. Overview ! 1. Overview ESP-WROOM-02D and ESP-WROOM-02U are ESP8266EX-based modules developed by Espressif. Compared to ESP-WROOM-02, the RF performance of ESP-WROOM-02D and ESP-WROOM-02U are optimized. Besides, ESP-WROOM-02U integrates a U.FL connector. Please see Chapter 8 for details of U.FL connector. Table 1-1. ESP-WROOM-02D vs. ESP-WROOM-02U Module ESP-WROOM-02D ESP-WROOM-02U Core ESP8266 ESP8266 Antenna Onboard antenna IPEX antenna Dimensions (18.00±0.10) x (20.00±0.10) x (3.20±0.10) (18.00±0.10) x (14.30±0.10) x (3.20±0.10) (unit: mm) See Figure 6-1 for details. See Figure 6-2 for details. Schematics See Figure 5-1 for details. See Figure 5-2 for details. 📖 Note: For more information on ESP8266EX, please refer to ESP8266EX Datasheet. Table 1-2. ESP-WROOM-02D/ESP-WROOM-02U Specifications Categories Certification Test Wi-Fi Items Specifications RF certification SRRC, FCC, CE (RED), IC, NCC, KCC, TELEC (MIC) Green certification RoHS, REACH Reliablity HTOL/HTSL/uHAST/TCT/ESD Wi-Fi protocols 802.11 b/g/n Frequency range 2.4 GHz ~ 2.5 GHz (2400M ~ 2483.5M) UART/HSPI/I2C/I2S/IR Remote Control Peripheral interface GPIO/PWM Hardware Espressif Operating voltage 2.7V ~ 3.6V Operating current Average: 80 mA Minimum current delivered by power supply 500 mA Operating temperature range -40°C ~ 85°C Storage temperature -40°C ~ 85°C External interface - ! /!22 1 2018.08 1. Overview ! Categories Software Espressif Items Specifications Wi-Fi mode Station/SoftAP/SoftAP + Station Security WPA/WPA2 Encryption WEP/TKIP/AES Firmware upgrade UART Download/OTA (via network)/Download and write firmware via host Software development Supports Cloud Server Development/SDK for custom firmware development Network protocols IPv4, TCP/UDP/HTTP/FTP User configuration AT Instruction Set, Cloud Server, Android/iOS app ! /!22 2 2018.08 2. Pin Description ! 2. Pin Description Figure 2-1 shows the pin distribution of the ESP-WROOM-02D. PCB ANTENNA 1 3V3 GND 18 2 EN IO16 17 3 IO14 TOUT 16 4 IO12 RST 15 5 IO13 IO5 14 6 IO15 GND 13 7 IO2 TXD 12 8 IO0 RXD 11 9 GND IO4 10 19GND ! Figure 2-1. ESP-WROOM-02D Pin Layout (Top View) 📖 Note: The pin layout of ESP-WROOM-02U is the same with that of ESP-WROOM-02D, but it has no keepout zone for PCB antenna. ESP-WROOM-02D and ESP-WROOM-02U have 18 pins. Please see the pin definitions in Table 2-1. Table 2-1. ESP-WROOM-02U/ESP-WROOM-02D Pin Definitions No. Pin Name Functional Description 3.3V power supply (VDD) Espressif 1 3V3 2 EN 📖 Note: It is recommended the maximum output current a power supply provides be of 500 mA or above. Chip enable pin. Active high. ! /!22 3 2018.08 2. Pin Description ! No. Pin Name Functional Description 3 IO14 GPIO14; HSPI_CLK 4 IO12 GPIO12; HSPI_MISO 5 IO13 GPIO13; HSPI_MOSI; UART0_CTS 6 IO15 7 IO2 8 IO0 GPIO15; MTDO; HSPICS; UART0_RTS Pull down. GPIO2; UART1_TXD Floating (internal pull-up) or pull up. GPIO0 • UART download: pull down. • Flash boot: floating or pull up. Espressif 9 GND GND 10 IO4 GPIO4 11 RXD 12 TXD 13 GND GND 14 IO5 GPIO5 15 RST Reset 16 TOUT It can be used to test the power-supply voltage of VDD3P3 (Pin3 and Pin4) and the input power voltage of TOUT (Pin6). These two functions cannot be used simultaneously. 17 IO16 GPIO16; used for Deep-sleep wake-up when connected to RST pin. 18 GND GND UART0_RXD, receive end in UART download; GPIO3 UART0_TXD, transmit end in UART download, floating or pull up; GPIO1 ! /!22 4 2018.08 3. Functional Description ! 3. Functional Description 3.1. CPU The ESP8266EX integrates a Tensilica L106 32-bit RISC processor, which achieves extralow power consumption and reaches a maximum clock speed of 160 MHz. The Real-Time Operating System (RTOS) and Wi-Fi stack allow 80% of the processing power to be available for user application programming and development. The CPU includes the interfaces as below: • Programmable RAM/ROM interfaces (iBus), which can be connected with memory controller, and can also be used to visit flash. • Data RAM interface (dBus), which can connected with memory controller. • AHB interface which can be used to visit the register. 3.2. Memory 3.2.1. Internal SRAM and ROM ESP8266EX Wi-Fi SoC integrates the memory controller and memory units including ROM and SRAM. MCU can access the memory units through iBus, dBus, and AHB interfaces. All memory units can be accessed upon request. A memory arbiter determines the running sequence in the arrival order of requests. According to our current version of SDK, the SRAM space available to users is assigned as follows: • RAM size < 50 kB, that is, when ESP8266EX is working in Station mode and connects to the router, available space in the Heap + Data sector is around 50 kB. • There is no programmable ROM in ESP8266EX, therefore, the user program must be stored in an external SPI flash. 3.2.2. SPI Flash ESP8266EX supports SPI flash. Theoretically speaking, ESP8266EX can support an upto-16-MB SPI flash. ESP-WROOM-02D and ESP-WROOM-02U currently integrate a 2-MB SPI flash. ESPWROOM-02U supports these SPI modes: Standard SPI, DIO (Dual I/O), DOUT (Dual Output), QIO (Quad I/O) and QOUT (Quad Output). Espressif ! /!22 5 2018.08 3. Functional Description ! 3.3. Crystal Oscillator ESP-WROOM-02U and ESP-WROOM-02D use a 26-MHz crystal oscillator. The accuracy of the crystal oscillator should be ±10 PPM. When using the download tool, please select the right type of crystal oscillator. In circuit design, capacitors C1 and C2 which connect to the earth are added to the input and output terminals of the crystal oscillator respectively. The values of the two capacitors can be flexible, ranging from 6 pF to 22 pF, however, the specific capacitive values depend on further testing of, and adjustment to, the overall performance of the whole circuit. Normally, the capacitive values of C1 and C2 are within 10 pF for the 26-MHz crystal oscillator. 3.4. Interface Description Table 3-1. Interface Description Interface Pin Functional Description HSPI IO12 (MISO), IO13 (MOSI), IO14 (CLK), IO15 (CS) Connects to SPI Flash, display screen, and MCU. PWM IO12 (R), IO15 (G),IO13 (B) Currently the PWM interface has four channels, but users can extend it to eight channels. PWM interface can realize the control of LED lights, buzzers, relays, electronic machines, etc. IR IO14 (IR_T), IO5 (IR_R) The functionality of the infrared remote control interface can be realized via software programming. The interface uses NEC coding, modulation, and demodulation. The frequency of the modulated carrier signal is 38 kHz. ADC TOUT Tests the power supply voltage of VDD3P3 (Pin3 and Pin4) and the input power voltage of TOUT (Pin6). However, these two functions cannot be used simultaneously. This interface is typically used in sensors. I2C IO14 (SCL), IO2 (SDA) Connects to external sensors and display screens, etc. Communicates with the UART device. Downloading: U0TXD + U0RXD or GPIO2 + U0RXD UART0: TXD (U0TXD), UART RXD (U0RXD), IO15 (RTS), IO13 (CTS) UART1: IO2 (TXD) Espressif Communicating: (UART0): U0TXD, U0RXD, MTDO (U0RTS), MTCK (U0CTS) Debugging: UART1_TXD (GPIO2) can be used to print debugging information. By default, UART0 will output some printed information when you power on ESP8266EX. If this issue influences some specific applications, users can exchange the inner pins of UART when initializing ESP8266EX, that is, exchange U0TXD and U0RXD with U0RTS and U0CTS. Users can connect MTDO and MTCK to the serial port of the external MCU to realize the communication. ! /!22 6 2018.08 3. Functional Description ! Interface Pin Functional Description I2S input: IO12 (I2SI_DATA) ; IO13 (I2SI_BCK ); I2S IO14 (I2SI_WS); Collects, processes and transmits audio data. I2S output: IO15 (I2SO_BCK ); IO3 (I2SO_DATA); IO2 (I2SO_WS ). Espressif ! /!22 7 2018.08 4. Electrical Characteristics ! 4. Electrical Characteristics 📖 Note: Unless otherwise specified, measurements are based on VDD = 3.3V, TA = 25°C. 4.1. Electrical Characteristics Table 4-1. Electrical Characteristics Parameter Symbol Min Typ Max Unit Storage temperatue - –40 Normal 85 ℃ Operating temperature - –40 20 85 ℃ Maximum soldering temperature (Condition: IPC/JEDEC J-STD-020) - - - 260 ℃ Supply voltage VDD 2.7 3.3 3.6 V Input logic level low VIL –0.3 - 0.25 VDD V Input logic level high VIH 0.75 VDD - VDD + 0.3 V Output logic level low VOL - - 0.1 VDD V Output logic level high VOH 0.8 VDD - - V 4.2. Wi-Fi Radio Table 4-2. Wi-Fi Radio Characteristics Description Min Typ Max Unit Input frequency 2412 - 2484 MHz Input reflection -　 - –10 dB Output Impedance - * - Ω Output Power PA output power at 72.2 Mbps 13 14 15 dBm PA output power in 11b mode 19.5 20 20.5 dBm –98 - dBm Sensitivity DSSS, 1 Mbps Espressif - ! /!22 8 2018.08 4. Electrical Characteristics ! Description Min Typ Max Unit CCK, 11 Mbps - –91 - dBm 6 Mbps (1/2 BPSK) - –93 - dBm 54 Mbps (3/4 64-QAM) - –75 - dBm HT20, MCS7 (65 Mbps, 72.2 Mbps) - –72 - dBm Adjacent channel rejection OFDM, 6 Mbps - 37 - dB OFDM, 54 Mbps - 21 - dB HT20, MCS0 - 37 - dB HT20, MCS7 - 20 - dB 📖 Note: For the module that uses an IPEX antenna, the output impedance is 50Ω. 4.3. Power Consumption The following power consumption data were obtained from the tests with a 3.3V power supply and a voltage stabilizer, in 25°C ambient temperature. All data are based on 50% duty cycle in continuous transmission mode. Table 4-3. Power Consumption Espressif Modes Min Typ Max Unit Tx 802.11b, CCK 11 Mbps, POUT = +17 dBm - 170 - mA Tx 802.11g, OFDM 54 Mbps, POUT = +15 dBm - 140 - mA Tx 802.11n, MCS7, POUT = +13 dBm - 120 - mA Rx 802.11b, 1024 bytes packet length , –80 dBm - 50 - mA Rx 802.11g, 1024 bytes packet length , –70 dBm - 56 - mA Rx 802.11n, 1024 bytes packet length , –65 dBm - 56 - mA Modem-sleep① - 15 - mA Light-sleep② - 0.9 - mA Deep-sleep③ - 20 - μA Power Off - 0.5 - μA ! /!22 9 2018.08 4. Electrical Characteristics ! 📖 Notes: ① Modem-sleep is used when such applications as PWM or I2S require the CPU to be working. In cases where Wi-Fi connectivity is maintained and data transmission is not required, the Wi-Fi Modem circuit can be shut down to save power, according to 802.11 standards (such as U-APSD). For example, in DTIM3, when ESP8266EX sleeps for 300 ms and wakes up for 3 ms to receive Beacon packages from AP, the overall average current consumption is about 15 mA. ② Light-sleep is used for applications whose CPU may be suspended, such as Wi-Fi switch. In cases where Wi-Fi connectivity is maintained and data transmission is not required, the Wi-Fi Modem circuit and CPU can be shut down to save power, according to 802.11 standards (such as U-APSD). For example, in DTIM3, when ESP8266EX sleeps for 300 ms and wakes up for 3 ms to receive Beacon packages from AP, the overall average current consumption is about 0.9 mA. ③ Deep-sleep is for applications that do not require Wi-Fi connectivity but only transmit data over long time lags, e.g., a temperature sensor that measures temperature every 100s. For example, when ESP8266EX sleeps for 300s then wakes up to connect to AP (taking about 0.3 ~ 1s), the overall average current consumption is far less than 1 mA. The current consumption of 20 μA was obtained at the voltage of 2.5V. Temperature (℃) 4.4. Reflow Profile Peak Temp. 235 ~ 250℃ 250 Preheating zone 150 ~ 200℃ 60 ~ 120s 217 200 Reflow zone !217℃ 60 ~ 90s Cooling zone -1 ~ -5℃/s Soldering time > 30s Ramp-up zone 1 ~ 3℃/s 100 50 25 Time (sec.) 0 0 50 100 150 200 250 Ramp-up zone — Temp.: 217℃ 7LPH60 ~ 90s; Peak Temp.: 235 ~ 250℃ (