LTC3882_15 Datasheet, PDF (83/104 Pages) Linear Technology – Dual Output PolyPhase Step-Down DC/DC Voltage Mode Controller with Digital Power System Management

LTC3882
PMBus COMMAND DETAILS (External Temperature Limits)
UT_FAULT_LIMIT
The UT_FAULT_LIMIT command sets the value of sensed external temperature, in degrees Celsius, which causes an
undertemperature fault.
This command has two data bytes in Linear_5s_11s format.
STATUS REPORTING
COMMAND NAME
CMD
CODE DESCRIPTION
DATA
TYPE PAGED FORMAT
STATUS_BYTE
0x78 One-byte channel status summary.
R/W Byte Y
Reg
STATUS_WORD
0x79 Two-byte channel status summary.
R/W Word Y
Reg
STATUS_VOUT
STATUS_IOUT
STATUS_INPUT
0x7A V_OUT fault and warning status.
0x7B I_OUT fault and warning status.
0x7C Input supply fault and warning status.
R/W Byte Y
Reg
R/W Byte Y
Reg
R/W Byte N
Reg
STATUS_TEMPERATURE
0x7D External temperature fault and warning
status.
R/W Byte Y
Reg
STATUS_CML
0x7E Communication, memory and logic fault and R/W Byte N
Reg
warning status.
STATUS_MFR_SPECIFIC
0x80 LTC3882-specific status.
R/W Byte Y
Reg
MFR_PADS_LTC3882
0xE5 State of selected LTC3882 pads.
R Word N
Reg
MFR_COMMON
0xEF LTC-generic device status reporting.
R Byte N
Reg
CLEAR_FAULTS
0x03 Clear all set fault bits.
Send Byte N
Refer to Figure 2 for a graphical depiction of these register contents and their relationships.
UNITS NVM
DEFAULT
VALUE
STATUS_BYTE
The STATUS_BYTE command returns a one-byte summary of the most critical faults.
STATUS_BYTE Message Contents:
BIT
STATUS BIT NAME MEANING
7*
BUSY
A fault was declared because the LTC3882 was unable to respond.
6
OFF
This bit is set if the channel is not providing power to its output, regardless of the reason, including simply not
being enabled.
5
VOUT_OV
An output overvoltage fault has occurred.
4
IOUT_OC
An output overcurrent fault has occurred.
3
VIN_UV
Not supported (LTC3882 returns 0).
2
TEMPERATURE A temperature fault or warning has occurred.
1
CML
A communications, memory or logic fault has occurred.
0*
NONE OF THE ABOVE A fault Not listed in bits[7:1] has occurred.
*ALERT can be asserted if either of these bits is set. They may be cleared by writing a 1 to their bit position in the STATUS_BYTE, in lieu of a CLEAR_FAULTS
command.
This command has one data byte.
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