Chip Silk Marking
Espressif chip silk marking provides information such as chip name, flash size, and operating temperature.
Marking Convention
Chip Silk Marking Diagram
Pin 1: Position of Pin 1.
Espressif Logo: Company logo.
Product Name: Specifies the chip name.
Date Code: WW is the week number of year YYYY. Example: Date Code “122017” stands for the 12th week of year 2017.
Flash Code is a code that indicates:
(Optional) Temperature and flash size.
The tracking information of the in-package flash.
The arrangement of the flash code can vary by product. Please see Flash Code and PSRAM Code Conventions for details.
PSRAM Code is a code that indicates:
(Optional) Temperature and PSRAM size.
The tracking information of the in-package PSRAM.
The arrangement of the PSRAM code can vary by product. Please see Flash Code and PSRAM Code Conventions for details.
Espressif Tracking Information: The second character of this code correlates to the chip revision. See the detailed mapping in ESP Chip Errata.
Flash Code and PSRAM Code Conventions
Based on the in-package flash or PSRAM, ESP32 chips can be divided into the following categories.
No Flash, No PSRAM
This section applies to ESP32 chips without any in-package flash or PSRAM. For such chips, flash code and PSRAM code are simply left empty.
Flash Code and PSRAM Code Diagram - No Flash, No PSRAM
In-package Flash, No PSRAM
This section applies to ESP32 chips with only in-package flash. For such chips, only the flash code is used. PSRAM code is left empty.
Flash Code and PSRAM Code Diagram - In-package Flash, No PSRAM
(Optional) Temperature (2 characters):
FH: 105 °C
FN: 85 °C
(Optional) Size (1 character):
2: 2 MB
4: 4 MB
8: 8 MB
Flash Tracking Information (7 characters).
Note
For ESP32-U4WDH, ESP32-PICO-V3 and ESP32-PICO-D4, the flash codes are not provided on the silk markings.
In-package PSRAM, No Flash
This section applies to ESP32 chips with only in-package PSRAM. For such chips, only the PSRAM code is used.
Flash Code and PSRAM Code Diagram - In-package PSRAM, No Flash
(Optional) Size (2 characters):
R2: 2 MB
R8: 8 MB
PSRAM Tracking Information (9 characters).
In-package Flash, In-package PSRAM
This section applies to ESP32 chips with both in-package flash and PSRAM. For such chips, both flash code and PSRAM code are used.
Flash Code and PSRAM Code Diagram - In-package Flash, In-package PSRAM
(Optional) Temperature (1 character):
H: 105 °C
N: 85 °C
(Optional) Flash Size (1 character):
4: 4 MB
8: 8 MB
(Optional) PSRAM Size (2 characters):
R2: 2 MB
R8: 8 MB
Flash Tracking Information (7 characters).
PSRAM Tracking Information (9 characters).
Note
For ESP32-PICO-V3-02, the flash code and PSRAM code are not provided on the silk markings.