ESP8266EX Datasheet Version 6.6 Espressif Systems Copyright © 2020 www.espressif.
About This Guide This document introduces the specifications of ESP8266EX. Release Notes Date Version Release Notes 2015.12 V4.6 Updated Chapter 3. 2016.02 V4.7 Updated Section 3.6 and Section 4.1. 2016.04 V4.8 Updated Chapter 1. 2016.08 V4.9 Updated Chapter 1. 2016.11 V5.0 Added Appendix Ⅱ “Learning Resources”. 2016.11 V5.1 Changed the power consumption during Deep-sleep from 10 μA to 20 μA in Table 5-2. 2016.11 V5.
Date 2018.09 Version V5.9 Release Notes • Update document cover; • Added a note for Table 1-1; • Updated Wi-Fi key features in Section 1.1; • Updated description of the Wi-Fi function in 3.5; • Updated pin layout diagram; • Fixed a typo in Table 2-1; • Removed Section AHB and AHB module; • Restructured Section Power Management; • Fixed a typo in Section UART; • Removed description of transmission angle in Section IR Remote Control; • Other optimization (wording).
Table of Contents 1. Overview ................................................................................................................................ 1 1.1. Wi-Fi Key Features .....................................................................................................................1 1.2. Specifications .............................................................................................................................2 1.3. Applications ...........................................
4.9. ADC (Analog-to-Digital Converter) ...........................................................................................17 5. Electrical Specifications ......................................................................................................19 5.1. Electrical Characteristics ..........................................................................................................19 5.2. RF Power Consumption .............................................................................
1. Overview $ 1. Overview Espressif’s ESP8266EX delivers highly integrated Wi-Fi SoC solution to meet users’ continuous demands for efficient power usage, compact design and reliable performance in the Internet of Things industry. With the complete and self-contained Wi-Fi networking capabilities, ESP8266EX can perform either as a standalone application or as the slave to a host MCU. When ESP8266EX hosts the application, it promptly boots up from the flash.
1. Overview $ 1.2. Specifications Table 1-1. Specifications Categories Items Parameters Certification Wi-Fi Alliance Protocols 802.11 b/g/n (HT20) Frequency Range 2.4 GHz ~ 2.5 GHz (2400 MHz ~ 2483.5 MHz) 802.11 b: +20 dBm Wi-Fi TX Power 802.11 g: +17 dBm 802.11 n: +14 dBm 802.11 b: –91 dbm (11 Mbps) Rx Sensitivity 802.11 g: –75 dbm (54 Mbps) 802.
1. Overview $ 1.3. Applications • Home appliances • Home automation • Smart plugs and lights • Industrial wireless control • Baby monitors • IP cameras • Sensor networks • Wearable electronics • Wi-Fi location-aware devices • Security ID tags • Wi-Fi position system beacons Espressif $3/$26 Submit Documentation Feedback 2020.
2. Pin Definitions $ 2. Pin Definitions GND EXT_RSTB RES12K VDDA VDDD XTAL_IN XTAL_OUT U0TXD U0RXD 33 32 31 30 29 28 27 26 25 Figure 2-1 shows the pin layout for 32-pin QFN package. VDDA 1 24 GPIO5 LNA 2 23 SD_DATA_1 VDD3P3 3 22 SD_DATA_0 VDD3P3 4 21 SD_CLK ESP8266EX VDDPST MTMS 16 17 GPIO4 8 15 XPD_DCDC GPIO0 SD_DATA_2 14 18 GPIO2 7 13 CHIP_EN MTDO SD_DATA_3 12 19 MTCK 6 11 TOUT VDDPST SD_CMD 10 20 MTDI 5 9 VDD_RTC $ Figure 2-1.
2. Pin Definitions $ Pin Name Type Function 4 VDD3P3 P Amplifier Power 2.5 V ~ 3.6 V 5 VDD_RTC P NC (1.1 V) ADC pin. It can be used to test the power-supply voltage of VDD3P3 (Pin3 and Pin4) and the input power voltage of TOUT (Pin 6). However, these two functions cannot be used simultaneously.
2. Pin Definitions $ Pin Name Type Function 31 RES12K I Serial connection with a 12 kΩ resistor and connect to the ground 32 EXT_RSTB I External reset signal (Low voltage level: active) 📖 Note: 1. GPIO2, GPIO0, and MTDO are used to select booting mode and the SDIO mode; 2. U0TXD should not be pulled externally to a low logic level during the powering-up. Espressif $6/$26 Submit Documentation Feedback 2020.
3. Functional Description $ 3. Functional Description The functional diagram of ESP8266EX is shown as in Figure 3-1. RF receive MAC Analog receive PMU Analog transmit VCO 1/2 Crystal Digital baseband RF transmit PLL UART GPIO Switch RF balun Registers Interface I2C I2S Sequencers SDIO PWM Accelerator PLL Bias circuits CPU ADC SPI SRAM PMU Flash $ Figure 3-1. Functional Block Diagram 3.1. CPU, Memory, and Flash 3.1.1.
3. Functional Description $ According to our current version of SDK, SRAM space available to users is assigned as below. • RAM size < 50 kB, that is, when ESP8266EX is working under the Station mode and connects to the router, the maximum programmable space accessible in Heap + Data section is around 50 kB. • There is no programmable ROM in the SoC. Therefore, user program must be stored in an external SPI flash. 3.1.3.
3. Functional Description $ Parameter Symbol Min Max Unit Frequency tolerance ΔFXO –15 15 ppm Frequency vs temperature (–25 °C ~ 75 °C) ΔFXO,Temp –15 15 ppm 3.2.2. External Clock Requirements An externally generated clock is available with the frequency ranging from 24 MHz to 52 MHz. The following characteristics are expected to achieve good performance of radio. Table 3-2. External Clock Reference Parameter Symbol Min Max Unit Clock amplitude VXO 0.8 1.
3. Functional Description $ Channel No. Frequency (MHz) Channel No. Frequency (MHz) 5 2432 12 2467 6 2437 13 2472 7 2442 14 2484 3.3.2. 2.4 GHz Receiver The 2.4 GHz receiver down-converts the RF signals to quadrature baseband signals and converts them to the digital domain with 2 high resolution high speed ADCs. To adapt to varying signal channel conditions, RF filters, automatic gain control (AGC), DC offset cancelation circuits and baseband filters are integrated within ESP8266EX. 3.3.3.
3. Functional Description $ 3.4.1. Wi-Fi Radio and Baseband The ESP8266EX Wi-Fi Radio and Baseband support the following features: • 802.11 b and 802.11 g • 802.11 n MCS0-7 in 20 MHz bandwidth • 802.11 n 0.4 μs guard-interval • up to 72.2 Mbps of data rate • Receiving STBC 2 x 1 • Up to 20.5 dBm of transmitting power • Adjustable transmitting power 3.4.2.
3. Functional Description $ Table 3-4. Power Consumption by Power Modes Power Mode Active (RF working) Description Wi-Fi TX packet Wi-Fi RX packet Power Consumption Please refer to Table 5-2. Modem-sleep① CPU is working 15 mA Light-sleep② - 0.9 mA Deep-sleep③ Only RTC is working 20 uA Shut down - 0.5 uA 📖 Notes: ① ② ③ Espressif Modem-sleep mode is used in the applications that require the CPU to be working, as in PWM or I2S applications. According to 802.
4. Peripheral Interface $ 4. Peripheral Interface 4.1. General Purpose Input/Output Interface (GPIO) ESP8266EX has 17 GPIO pins which can be assigned to various functions by programming the appropriate registers. Each GPIO PAD can be configured with internal pull-up or pull-down (XPD_DCDC can only be configured with internal pull-down, other GPIO PAD can only be configured with internal pull-up), or set to high impedance.
4. Peripheral Interface $ 4.3. Serial Peripheral Interface (SPI/HSPI) ESP8266EX has two SPIs. • One general Slave/Master SPI • One general Slave/Master HSPI Functions of all these pins can be implemented via hardware. 4.3.1. General SPI (Master/Slave) Table 4-2.
4. Peripheral Interface $ 4.4. I2C Interface ESP8266EX has one I2C, which is realized via software programming, used to connect with other microcontrollers and other peripheral equipments such as sensors. The pin definition of I2C is as below. Table 4-4. Pin Definitions of I2C Pin Name Pin Num IO Function Name MTMS 9 IO14 I2C_SCL GPIO2 14 IO2 I2C_SDA Both I2C Master and I2C Slave are supported.
4. Peripheral Interface $ Table 4-6. Pin Definitions of UART Pin Type UART0 UART1 Pin Name Pin Num IO Function Name U0RXD 25 IO3 U0RXD U0TXD 26 IO1 U0TXD MTDO 13 IO15 U0RTS MTCK 12 IO13 U0CTS GPIO2 14 IO2 U1TXD SD_D1 23 IO8 U1RXD Data transfers to/from UART interfaces can be implemented via hardware. The data transmission speed via UART interfaces reaches 115200 x 40 (4.5 Mbps). UART0 can be used for communication. It supports flow control.
4. Peripheral Interface $ frequency is 1 kHz, the duty ratio will be 1/22727, and a resolution of over 14 bits will be achieved at 1 kHz refresh rate. 4.8. IR Remote Control ESP8266EX currently supports one infrared remote control interface. For detailed pin definitions, please see Table 4-8 below. Table 4-8.
4. Peripheral Interface $ Hardware Design RF Initialization Parameter The input voltage range is 0 to 1.0 V when TOUT is connected to external circuit. The value of the 107th byte of esp_init_data_default.bin (0 ~ 127 bytes), vdd33_const must be set to the real power supply voltage of Pin3 and Pin4. The unit and effective value range of vdd33_const is 0.1 V and 18 to 36, respectively, thus making the working power voltage range of ESP8266EX between 1.8 V and 3.6 V.
5. Electrical Specifications $ 5. Electrical Specifications 5.1. Electrical Characteristics Table 5-1. Electrical Characteristics Parameters Conditions Min Typical Max Unit Operating Temperature Range - –40 Normal 125 ℃ Maximum Soldering Temperature IPC/JEDEC JSTD-020 - - 260 ℃ Working Voltage Value - 2.5 3.3 3.6 V - –0.3 - 0.25 VIO VIL VIH I/O 0.75 VIO VOL - VOH - 3.6 - 0.8 VIO IMAX 0.
5. Electrical Specifications $ Table 5-2. Description of ESP8266EX Power-up and Reset Timing Parameters Description Min Max Unit t1 The rise-time of VDD33 10 2000 μs t2 The rise-time of EXT_RSTB 0 2 ms t3 EXT_RSTB goes high after VDD33 0.1 - ms t4 The rise-time of CHIP_EN 0 2 ms t5 CHIP_EN goes high after EXT_RSTB 0.1 - ms 5.2. RF Power Consumption Unless otherwise specified, the power consumption measurements are taken with a 3.0 V supply at 25 °C of ambient temperature.
5. Electrical Specifications $ 5.3. Wi-Fi Radio Characteristics The following data are from tests conducted at room temperature, with a 3.3 V power supply. Table 5-3. Wi-Fi Radio Characteristics Parameters Min Typical Max Unit Input frequency 2412 - 2484 MHz Output impedance - 39 + j6 - Ω Output power of PA for 72.2 Mbps 15.5 16.5 17.5 dBm Output power of PA for 11b mode 19.5 20.5 21.
6. Package Information $ 6. Package Information ! Figure 6-1. ESP8266EX Package Espressif $22/$ 26 Submit Documentation Feedback 2020.
Appendix Ⅰ $ I. Appendix - Pin List For detailed pin information, please see ESP8266 Pin List. • Digital Die Pin List • Buffer Sheet • Register List • Strapping List 📖 Notes: • • • • Espressif INST_NAME refers to the IO_MUX REGISTER defined in eagle_soc.h, for example MTDI_U refers to PERIPHS_IO_MUX_MTDI_U. Net Name refers to the pin name in schematic. Function refers to the multifunction of each pin pad. Function number 1 ~ 5 correspond to FUNCTION 0 ~ 4 in SDK.
Appendix Ⅱ $ II. Appendix - Learning Resources II.1. Must-Read Documents • ESP8266 Quick Start Guide Description: This document is a quick user guide to getting started with ESP8266. It includes an introduction to the ESP-LAUNCHER, instructions on how to download firmware to the board and run it, how to compile the AT application, as well as the structure and debugging method of RTOS SDK. Basic documentation and other related resources for the ESP8266 are also provided.
Appendix Ⅱ $ Description: This webpage provides links to both the ESP8266 flash download tools and the ESP8266 performance evaluation tools. • ESP8266 Apps • ESP8266 Certification and Test Guide • ESP8266 BBS • ESP8266 Resources Espressif $25/$ 26 Submit Documentation Feedback 2020.
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