Datasheet

LTC2974
42
2974fc
For more information www.linear.com/LTC2974
MFR_EE_UNLOCK Data Contents
BIT(S) SYMBOL OPERATION
b[7:0] Mfr_ee_unlock[7:0] To unlock user EEPROM space for Mfr_ee_erase and Mfr_ee_data read or write operations with PEC allowed:
Write 0x2b followed by 0xd4.
To unlock user EEPROM space for Mfr_ee_erase and Mfr_ee_data read or write operations with PEC required:
Write 0x2b followed by 0xd5.
To unlock user and manufacturer EEPROM space for Mfr_ee_data read only operations with PEC allowed:
Write 0x2b, followed by 0x91 followed by 0xe4.
To unlock user and manufacturer EEPROM space for Mfr_ee_data read only operations with PEC required:
Write 0x2b, followed by 0x91 followed by 0xe5.
MFR_EE_ERASE
The MFR_EE_ERASE command is used to erase the entire contents of the user EEPROM space and configures this
space to accept new program data. Writing values other than 0x2B will lock the part. Reads return the last value written.
MFR_EE_ERASE Data contents
BIT(S) SYMBOL OPERATION
b[7:0] Mfr_ee_erase[7:0] To erase the user EEPROM space and configure to accept new data:
1) Use the appropriate Mfr_ee_unlock sequence to configure for Mfr_ee_erase commands with or without PEC.
2) Write 0x2B to Mfr_ee_erase.
The part will indicate it is busy erasing the EEPROM by the mechanism detailed below.
MFR_EE_DATA
The MFR_EE_DATA command allows the user to transfer data directly to or from the EEPROM without affecting RAM
space.
To read the user EEPROM space issue the appropriate Mfr_ee_unlock command and perform Mfr_ee_data reads until
the EEPROM has been completely read. Extra reads will lock the part and return zero. The first read returns the 16-bit
EEPROM packing revision ID that is stored in ROM. The second read returns the number of 16-bit words available;
this is the number of reads or writes to access all memory locations. Subsequent reads return EEPROM data starting
with lowest address.
To write to the user EEPROM space issue the appropriate Mfr_ee_unlock and Mfr_ee_erase commands followed by
successive Mfr_ee_data word writes until the EEPROM is full. Extra writes will lock the part. The first write is to the
lowest address.
Mfr_ee_data reads and writes must not be mixed.
pMbus coMManD DescripTion