Chip Revision Identification

[中文]

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]

Table 1 Chip Revision Identification by eFuse Bits
	eFuse Bit	Chip Revision
	eFuse Bit	v0.0	v0.1	v0.2
Major Number	EFUSE_RD_MAC_SPI_SYS_5_REG[25]	0	0	0
Major Number	EFUSE_RD_MAC_SPI_SYS_5_REG[24]	0	0	0
Minor Number	EFUSE_RD_MAC_SPI_SYS_5_REG[23]	0	0	0
	EFUSE_RD_MAC_SPI_SYS_3_REG[20]	0	0	0
	EFUSE_RD_MAC_SPI_SYS_3_REG[19]	0	0	1
	EFUSE_RD_MAC_SPI_SYS_3_REG[18]	0	1	0

Chip Marking

Espressif Tracking Information line in chip marking

Table 2 Chip Revision Identification by Chip Marking
Chip Revision	Espressif Tracking Information
v0.0	X `A` XXXXXX
v0.1	X `B` XXXXXX
v0.2	X `C` XXXXXX

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

v0.0

— ¹

v0.1

M0 XXXX

v0.2

MC XXXX

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.

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.