Chip Revision Identification
Espressif is introducing a new vM.X numbering scheme to indicate chip revisions. This guide outlines the structure of this scheme and provides information on chip errata and additional identification methods.
Chip Revision Numbering Scheme
The new numbering scheme vM.X consists of the major and minor numbers described below.
M – Major number, indicating the major revision of the chip product. If this number changes, it means the software used for the previous version of the product is incompatible with the new product, and the software version shall be upgraded for the use of the new product.
X – Minor number, indicating the minor revision of the chip product. If this number changes, it means the software used for the previous version of the product is compatible with the new product, and there is no need to upgrade the software.
The vM.X scheme replaces previously used chip revision schemes, including ECOx numbers, Vxxx, and other formats if any.
Primary Identification Methods
eFuse Bits
The chip revision is encoded using two eFuse fields:
EFUSE_RD_MAC_SPI_SYS_5_REG[25:23]
EFUSE_RD_MAC_SPI_SYS_3_REG[20:18]
eFuse Bit |
Chip Revision |
||||||
|---|---|---|---|---|---|---|---|
v0.0 |
v0.1 |
v0.2 |
v0.3 |
v0.4 |
v1.1 |
||
Major Number |
EFUSE_RD_MAC_SPI_SYS_5_REG[25] |
0 |
0 |
0 |
0 |
0 |
0 |
EFUSE_RD_MAC_SPI_SYS_5_REG[24] |
0 |
0 |
0 |
0 |
0 |
1 |
|
Minor Number |
EFUSE_RD_MAC_SPI_SYS_5_REG[23] |
0 |
0 |
0 |
0 |
0 |
0 |
EFUSE_RD_MAC_SPI_SYS_3_REG[20] |
0 |
0 |
0 |
0 |
1 |
0 |
|
EFUSE_RD_MAC_SPI_SYS_3_REG[19] |
0 |
0 |
1 |
1 |
0 |
0 |
|
EFUSE_RD_MAC_SPI_SYS_3_REG[18] |
0 |
1 |
0 |
1 |
0 |
1 |
|
Chip Marking
Espressif Tracking Information line in chip marking
Figure 1 Chip Marking Diagram
Chip Revision |
Main Die |
|---|---|
v0.0 |
X |
v0.1 |
X |
v0.2 |
X |
v0.3 |
X |
v0.4 |
X |
v1.1 |
X |
Module Marking
Specification Identifier line in module marking
Figure 2 Module Marking Diagram
Table 3 Chip Revision Identification by Module Marking Chip Revision
Specification Identifier 1
v0.0
—
v0.1
—
v0.2
—
v0.3
XXXXXXv0.4
M4XXXXv1.1
—
1 Missing specification identifier “—” means modules with this chip revision are not mass produced.
Additional Identification Methods
Date Code
Some errors in the chip product don’t need to be fixed at the silicon level, or in other words in a new chip revision.
In this case, the chip may be identified by Date Code in chip marking (see Chip Marking Diagram). For more information, please refer to Espressif Chip Packaging Information.
PW Number
Modules built around the chip may be identified by PW Number in product label (see Module Product Label). For more information, please refer to Espressif Module Packaging Information.
Figure 3 Module Product Label
Note
Please note that PW Number is only provided for reels packaged in aluminum moisture barrier bags (MBB).
ESP-IDF Release Compatibility
Information about ESP-IDF release that supports a specific chip revision is provided in Compatibility Between ESP-IDF Releases and Revisions of Espressif SoCs.