Manual

MAX15301 PMBus Command Set User’s Guide
Rev 1 Page 42 of 53
SECURITY_LEVEL
Reference:
Maxim Specific
Lockable:
N/A
Command Code:
0xE6
Format:
Direct
Data Bytes:
1
Units:
N/A
Transfer:
Read Byte
Factory Value:
0x00
Description/Notes:
The MAX15301 provides two levels of password protection for all writeable PMBus commands, on a
per-command basis. The SECURITY_LEVEL command value shows the present security level as follows:
SECURITY_LEVEL Description
0x00 No write access to commands locked by USER_CONF or MANUF_CONF
0x01 Write access granted to commands locked by USER_CONF
0x02 Write access granted to commands locked by MANUF_CONF and USER_CONF
Note that SECURITY_LEVEL is 0 until a value is written to USER_PASSWD or MANUF_PASSWD that
matches the working-memory value of USER_LOCK or MANUF_LOCK respectively.
When the working-memory value of USER_LOCK is written to USER_PASSWD, SECURITY_LEVEL is set
to 1.
When the working-memory value of MANUF_LOCK is written to MANUF_PASSWD, SECURITY_LEVEL is
set to 2.
Writing a “mismatched” (or wrong) value of USER_PASSWD or MANUF_PASSWD causes
SECURITY_LEVEL to reset to 0.
The values of USER_LOCK and USER_CONF can only be changed when SECURITY_LEVEL is 1 or 2.
The values of MANUF_LOCK and MANUF_CONF can only be changed when SECURITY_LEVEL is 2.