www.espressif.com
Version 1.0
Espressif Systems
Copyright © 2019
ESP-WROOM-02
Datasheet (for Russian Market)
About This Guide
This document provides introduction to the specifications of ESP-WROOM-02 hardware.
Release Notes
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.
Date
Version
Release notes
2019.01
V1.0
First release.
Table of Contents
1. Overview 1 ................................................................................................................................
2. Pin Description 3 ......................................................................................................................
3. Functional Description 5 ..........................................................................................................
3.1. MCU!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. Dimensions 14 ..........................................................................................................................
7. Recommended PCB Land Pattern 15 .....................................................................................
A. Appendix—Learning Resources 16 .........................................................................................
A.1. Must-Read Documents!16"..........................................................................................................
A.2. Must-Have Resources!17............................................................................................................
1. Overview
1. Overview
Espressif provides the SMD module—ESP-WROOM-02 that integrates ESP8266EX. The
module has been adjusted to get the best RF performance. We recommend using ESP-
WROOM-02 for tests or for further development.
The module size is (18.00±0.10) mm x (20.00±0.10) mm x (2.80±0.10) mm. The type of
flash used on this module is an SPI flash with a package size of SOP 8-150 mil. The gain of
the on-board PCB antenna is 2 dBi.
Figure 1-1. ESP-WROOM-02 Module!
📖 Note:
For more information on ESP8266EX, please refer to ESP8266EX Datasheet.
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1. Overview
Table 1-1. ESP-WROOM-02 Specifications
Categories
Items
Specifications
Certification
RF certification
SRRC, FCC, CE (RED), IC, NCC, KCC, TELEC (MIC)
Wi-Fi certifaction
Wi-Fi Alliance
Green certification
RoHS, REACH
Test
Reliablity
HTOL/HTSL/uHAST/TCT/ESD
Wi-Fi
Wi-Fi protocols
802.11 b/g/n
Frequency range
2400 MHz ~ 2483.5 MHz
Hardware
Peripheral interface
UART/HSPI/I2C/I2S/IR Remote Control
GPIO/PWM
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
Package size
(18.00±0.10) mm x (20.00±0.10) mm x (2.80±0.10) mm
External interface
-
Software
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
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2. Pin Description
2. Pin Description
Figure 2-1 shows the pin distribution of the ESP-WROOM-02.
!
Figure 2-1. ESP-WROOM-02 Pin Layout (Top View)
ESP-WROOM-02 has 18 pins. Please see the pin definitions in Table 2-1.
19GND
PCB ANTENNA
GND
IO16
TOUT
RST
IO5
GND
TXD
RXD
IO4
3V3
EN
IO14
IO12
IO13
IO15
IO2
IO0
GND
9
8
7
6
5
4
3
2
1
10
11
12
13
14
15
16
17
18
Table 2-1. ESP-WROOM-02 Pin Definitions
No.
Pin Name
Functional Description
1
3V3
3.3V power supply (VDD)
📖 Note:
It is recommended the maximum output current a power supply
provides be of 500 mA or above.
2
EN
Chip enable pin. Active high.
3
IO14
GPIO14; HSPI_CLK
4
IO12
GPIO12; HSPI_MISO
5
IO13
GPIO13; HSPI_MOSI; UART0_CTS
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2. Pin Description
6
IO15
GPIO15; MTDO; HSPICS; UART0_RTS
Pull down.
7
IO2
GPIO2; UART1_TXD
Floating (internal pull-up) or pull up.
8
IO0
GPIO0
•UART download: pull down.
•Flash boot: floating or pull up.
9
GND
GND
10
IO4
GPIO4
11
RXD
UART0_RXD, receive end in UART download;
GPIO3
12
TXD
UART0_TXD, transmit end in UART download, floating or pull up;
GPIO1
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
No.
Pin Name
Functional Description
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3. Functional Description
3. Functional Description
3.1. MCU
ESP8266EX integrates a Tensilica L106 32-bit RISC processor, which achieves extra-low
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 memory controller and memory units including SRAM
and ROM. MCU can access the memory units through iBus, dBus, and AHB interfaces. All
memory units can be accessed upon request, while a memory arbiter will decide the
running sequence according to the time when these requests are received by the
processor.
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, 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.
3.2.2. SPI Flash
ESP8266EX uses external SPI flash to store user programs, and supports up to 16 MB
memory capacity theoretically.
ESP-WROOM-02 currently integrates a 2-MB SPI flash. ESP-WROOM-02 supports these
SPI modes: Standard SPI, DIO (Dual I/O), DOUT (Dual Output), QIO (Quad I/O) and QOUT
(Quad Output).
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3. Functional Description
3.3. Crystal Oscillator
ESP-WROOM-02 uses 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.
UART
UART0: TXD (U0TXD),
RXD (U0RXD), IO15
(RTS), IO13 (CTS)
UART1: IO2 (TXD)
Communicates with the UART device.
Downloading: U0TXD + U0RXD or GPIO2 + U0RXD
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.
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3. Functional Description
I2S
I2S input:
IO12 (I2SI_DATA) ;
IO13 (I2SI_BCK );
IO14 (I2SI_WS);
Collects, processes and transmits audio data.
I2S output:
IO15 (I2SO_BCK );
IO3 (I2SO_DATA);
IO2 (I2SO_WS ).
Interface
Pin
Functional Description
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4. Electrical Characteristics
4. Electrical Characteristics
4.1. Electrical Characteristics
4.2. Wi-Fi Radio
📖 Note:
Unless otherwise specified, measurements are based on VDD = 3.3V, TA = 25°C.
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
Table 4-2. Wi-Fi Radio Characteristics
Description
Min
Typ
Max
Unit
Frequency range
2400
-
2483.5
MHz
Input reflection
-　
-
–10
dB
Output Power
PA output power at 72.2 Mbps
13
14
15
dBm
PA output power in 11b mode
18.5
19
19.5
dBm
Sensitivity
DSSS, 1 Mbps
-
–98
-
dBm
CCK, 11 Mbps
-
–91
-
dBm
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4. Electrical Characteristics
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.
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
Description
Min
Typ
Max
Unit
Table 4-3. Power Consumption
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
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4. Electrical Characteristics
4.4. Reflow Profile
!
Figure 4-1. ESP-WROOM-02 Reflow Profile
📖 Notes:
①Modem-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.
②Light-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, 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.
③Deep-sleep is for applications that do not require Wi-Fi connectivity and 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.
50 150
0
25
1 ~ 3℃/s
0
200
250
200
-1 ~ -5℃/s
Cooling zone
100
217
50
100 250
Reflow zone
!217℃ 60 ~ 90s
Temperature (℃)
Preheating zone
150 ~ 200℃ 60 ~ 120s
Ramp-up zone
Peak Temp.
235 ~ 250℃
Soldering time
> 30s
Time (sec.)
Ramp-up zone — Temp.: <150℃ Time: 60 ~ 90s Ramp-up rate: 1 ~ 3℃/s
Preheating zone — Temp.: 150 ~ 200℃ Time: 60 ~ 120s Ramp-up rate: 0.3 ~ 0.8℃/s
Reflow zone — Temp.: >217℃ 7LPH60 ~ 90s; Peak Temp.: 235 ~ 250℃ (<245℃ recommended) Time: 30 ~ 70s
Cooling zone — Peak Temp. ~ 180℃ Ramp-down rate: -1 ~ -5℃/s
Solder — Sn&Ag&Cu Lead-free solder (SAC305)
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4. Electrical Characteristics
4.5. Electrostatic Discharge
Table 4-4. Electrostatic Discharge Parameters
Name
Symbol
Reference
Level
Max
Unit
Electrostatic Discharge
(Human - Body Model)
VESD
(HBM)
Temperature: 23 ± 5℃
Based$on ANSI/ESDA/JEDEC JS - 001 - 2014
2
2000
V
Electrostatic Discharge
(Charged - Device Model)
VESD
(CDM)
Temperature: 23 ± 5℃
Based$on JEDEC EIA/JESD22 - C101F
C2
500
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5. Schematics
5. Schematics
!
Figure 5-1. ESP-WROOM-02 Schematics
GPIO15
RST
SD_D1
SD_D0
SD_CLK
SD_CMD
SD_D3
SD_D2
SD_CLK
SD_CMD
SD_D2
UTXD
WIFI_ANT
GPIO14
GPIO12
URXD
GPIO13
GPIO16
GPIO0
CH_PU
GPIO2
GPIO4
GPIO5
CH_PU
GPIO14
GPIO12
GPIO13
GPIO15
GPIO2
GPIO0
GPIO4
GPIO5
URXD
UTXD
RST
TOUT
GPIO16
TOUT
SD_D3
SD_D0
SD_D1
GND
GND
VDD33
GND
GNDGND
GND
GND
VDD33
GND
VDD33
GND
GND
GND
GND
VDD33
GND
GND
GND
VDD33
GND
GND
GND
Pin.1
3V3
Pin.2
CH_PU/EN
Pin.3
IO14
Pin.4
IO12
Pin.5
IO13
Pin.6
IO15
Pin.7
IO2
Pin.8
IO0
Pin.9
GNDPin.10
IO4
Pin.11
RXD
Pin.12
TXD
Pin.13
GND
Pin.14
IO5
Pin.15
RST
Pin.16
TOUT
Pin.17
IO16
Pin.18
GND
Pin.19
GND(P_GND)
ANT1
1
2
C2
10pF
D1
ESD3.3V88D-C
R1
12K±1%
C1
10pF
C3
0.1uF
C4 8.2pF
U3
FLASH
/CS
1
DO 2
/WP 3
GND
4
DI 5
CLK
6
/HOLD
7
VCC 8
L1
2.4pF
R3 200
C6
1uF
U1
26MHz ±10ppm
XIN
1
GND
2XOUT 3
GND 4
U2
ESP8266EX
VDDA
1
LNA
2
VDD3P3
3
VDD3P3
4
VDD_RTC
5
TOUT
6
CHIP_EN
7
XPD_DCDC
8
MTMS
9
MTDI
10
VDDPST
11
MTCK
12
MTDO
13
GPIO2
14
GPIO0
15
GPIO4
16
VDDPST17
SD_DATA_2 18
SD_DATA_3 19
SD_CMD 20
SD_CLK 21
SD_DATA_0 22
SD_DATA_1 23
GPIO5 24
U0RXD 25
U0TXD 26
XTAL_OUT 27
XTAL_IN 28
VDDD 29
VDDA 30
RES12K31
EXT_RSTB 32
GND 33
C5
10uF
L2
1.5nH
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5. Schematics
!
Figure 5-2. ESP-WROOM-02 Peripheral Schematics
EN
IO14
IO12
IO13
IO15
IO2
IO0
IO16
IO5
IO4
ADC
RXD
RST
TXD
VDD33
GND
VDD33
GND
GND
GNDGND
GND
GND
J2
BOOT OPTION
1
2
U1
ESP_WROOM_02
3V3
1
EN
2
IO14
3
IO12
4
IO13
5
IO15
6
IO2
7
IO0
8
GND1
9IO4 10
RXD 11
TXD 12
GND2 13
IO5 14
RST 15
TOUT 16
IO16 17
GND3 18
P_GND 19
J1
UART DOWNLOAD
1
2
3
C2 0.1uF
C3 0.1uF
R2 10K
C1 10uF
R1
10K
📖 Note:
Soldering Pad 19 to the Ground of the base board is not necessary for a satisfactory thermal
performance. If users do want to solder it, they need to ensure that the correct quantity of soldering paste
is applied.
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6. Dimensions
6. Dimensions
!
Figure 6-1. Dimensions of ESP-WROOM-02!
PCB Thickness
Module Thickness
Module Length
Unit: mm
Module Width
Top View Side View Bottom View
12.00±0.10
12.30±0.10
15.65±0.10
0.90±0.10
0.85±0.1
0.90±0.10
20.00±0.10
20.00±0.10
18.00±0.10 18.00±0.10
ESP-WROOM-02 DIMENSIONS
6.00±0.10
Antenna Area
󳊺
1.00±0.10
0.90±0.10
0.80±0.10
4.30±0.10
4.30±0.10
2.80±0.10
5.73±0.10
4.17±0.10
1.50±0.10
12.00±0.10
1.50±0.10
0.90±0.10
0.45±0.10
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7. Recommended PCB Land Pattern
7. Recommended PCB Land
Pattern
!
Figure 7-1. Recommended PCB Land Pattern of ESP-WROOM-02
Unit:mm
7.1
1.5x8=12
20
6
1.5
17.5
4
4.29
4
0.9
1
910
18
7.1
18
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Appendix A
A. Appendix—Learning
Resources
A.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, how to download firmware on to the
board and run it, how to compile the AT application, structure and the debugging
method of RTOS SDK. Basic documentation and other related resources for the
ESP8266 are also provided.
•ESP8266 SDK Getting Started Guide
Description: This document takes ESP-LAUNCHER and ESP-WROOM-02 as examples
to introduce how to use ESP8266 SDK. The contents include preparations before
compilation, SDK compilation and firmware download.
•ESP-WROOM-02 PCB Design and Module Placement Guide
Description: The ESP-WROOM-02 module is designed to be soldered to a host PCB.
This document compares six different placements of the antenna on a host board and
provides notes on designing PCB.
•ESP8266 Hardware Resources
Description: This zip package includes manufacturing specifications of the ESP8266
board and the modules, manufacturing BOM and schematics.
•ESP8266 AT Command Examples
Description: This document introduces some specific examples of using Espressif AT
commands, including single connection as a TCP Client, UDP transmission and
transparent transmission, and multiple connection as a TCP server.
•ESP8266 AT Instruction Set
Description: This document provides lists of AT commands based on
ESP8266_NONOS_SDK, including user-defined AT commands, basic AT commands,
Wi-Fi AT commands and TCP/IP-related AT commands. It also introduces the
downloading of AT firmware into flash.
•TCP/UDP UART Passthrough Test Demonstration
Description: This guide is intended to help users run a TCP & UDP passthrough test on
the ESP8266 IoT platform.
•FAQ
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Appendix A
A.2. Must-Have Resources
•ESP8266 SDKs
Description: This website page provides links to the latest version of ESP8266 SDK and
the older ones.
•ESP8266 Tools
Description: This website page provides links to the ESP8266 flash download tools and
ESP8266 performance evaluation tools.
•ESP8266 App
•ESP8266 Certification and Test Guide
•ESP8266 BBS
•ESP8266 Resources!
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Disclaimer and Copyright Notice
Information in this document, including URL references, is subject to change without
notice.
THIS DOCUMENT IS PROVIDED AS IS WITH NO WARRANTIES WHATSOEVER,
INCLUDING ANY WARRANTY OF MERCHANTABILITY, NON-INFRINGEMENT, FITNESS
FOR ANY PARTICULAR PURPOSE, OR 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.
Copyright © 2019 Espressif Inc. All rights reserved.
Espressif IoT Team"
www.espressif.com