Datasheet
LTC3880/LTC3880-1
81
3880fc
For more information www.linear.com/LTC3880
PMBus
COMMAND DETAILS
• Sets the VIN Overvoltage Fault bit in the STATUS_INPUT command, and
• Notifies the host by asserting ALERT pin
This command has one data byte.
Fault Responses Output Voltage
COMMAND NAME CMD CODE DESCRIPTION TYPE PAGED
DATA
FORMAT UNITS NVM
DEFAULT
VALUE
VOUT_OV_FAULT_RESPONSE 0x41 Action to be taken by the device when an
output overvoltage fault is detected.
R/W Byte Y Reg Y 0xB8
VOUT_UV_FAULT_RESPONSE 0x45 Action to be taken by the device when an
output undervoltage fault is detected.
R/W Byte Y Reg Y 0xB8
TON_MAX_FAULT_
RESPONSE
0x63 Action to be taken by the device when a
TON_MAX_FAULT event is detected.
R/W Byte Y Reg Y 0xB8
VOUT_OV_FAULT_RESPONSE
The VOUT_OV_FAULT_RESPONSE command instructs the device on what action to take in response to an output
overvoltage fault. The data byte is in the format given in Table 5.
The device also:
• Sets the VOUT_OV bit in the STATUS_BYTE
• Sets the VOUT bit in the STATUS_WORD
• Sets the VOUT Overvoltage Fault bit in the STATUS_VOUT command
• Notifies the host by asserting ALERT pin
The only value recognized for this command are:
0x80–The device shuts down (disables the output) and the unit does not attempt to retry. The output remains disabled
until the fault is cleared (PMBus, Part II, Section 10.7).
0xB8–The device shuts down (disables the output) and device attempts retry continuously, without limitation, until
it is commanded OFF (by the RUN pin or OPERATION command or both), bias power is removed, or another fault
condition causes the unit to shut down.
0x4n The device shuts down and the unit does not attempt to retry. The output remains disabled until the part is com
-
manded OFF then ON or the RUN pin is asserted low then high or RESET through the command or removal of VIN.
The OV fault must remain active for a period of n • 10µs, where n is a value from 0 to 7.
0x78+n The device shuts down and the unit attempts to retry continuously until either the fault condition is cleared
or the part is commanded OFF then ON or the RUN pin is asserted low then high or RESET through the command or
removal of VIN. The OV fault must remain active for a period of n • 10µs, where n is a value from 0 to 7.
Any other value will result in a CML fault and the write will be ignored.
This command has one data byte.