About This Guide
The guidelines outline recommended design practices when developing standalone or add-
on systems based on the ESP8266 series of products, including the ESP8266EX, the ESP-
WROOM modules, and ESP-LAUNCHER—the development board.
The document is structured as follows:
Hardware description of the ESP8266EX, including technical
speciﬁcations, pin deﬁnitions, layout, and typical applications.
Technical description of ESP-LAUNCHER with a built-in
Technical description of ESP-WROOM-01 and ESP-WROOM-02
with built-in ESP8266EX.
Sections 1.5.2, 1.5.3 & 1.6 updated.
Section 3.1 updated.
Section 2.1 updated.
Changed the minimum working voltage of ESP8266EX from 3.0V to 2.5V.
Updated Table 1-1.
Changed the chip output impedance from 50Ω to 39+j6 Ω;
Stated that Flash1 and Flash2 on ESP-LAUNCHER are both 32 Mbit;
Updated Section 1.4.5.
Updated Section 1.4.2;
Added ESP-WROOM-02 module's dimensional tolerance.
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