Datasheet

LTC3880/LTC3880-1
67
3880fc
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OPERATION
The OPERATION command is used to turn the unit on and off in conjunction with the input from the RUNn pins. It
is also used to cause the unit to set the output voltage to the upper or lower MARGIN VOLTAGEs. The unit stays in
the commanded operating mode until a subsequent OPERATION command or change in the state of the RUNn pin
instructs the device to change to another mode. If the part is stored in the MARGIN_LOW/HIGH state, the next RESET
or POWER_ON cycle will ramp to that state. If the OPERATION command is modified, for example ON is changed to
MARGIN_LOW, the output will move at a fixed slope set by the VOUT_TRANSITION_RATE.
Margin High (Ignore Faults) and Margin Low (Ignore Faults) operations are not supported by the LTC3880.
The part defaults to the ON state.
This command has one data byte.
Table 4. OPERATION Command Detail Register OPERATION Data Contents
When On_Off_Config_Use_PMBus Enables Operation_Control
SYMBOL Action Value
BITS
FUNCTION
Turn off immediately 0x00
Turn on 0x80
Margin Low 0x98
Margin High 0xA8
Sequence off 0x40
OPERATION Data Contents When On_Off_Config is Configured Such That
OPERATION Command Is Not Used to Command Channel On or Off
SYMBOL Action Value
BITS
FUNCTION
Output at Nominal 0x80
Margin Low 0x98
Margin High 0xA8
Note: Attempts to write a reserved value will cause a CML fault.
MFR_RESET
This command provides a means by which the user can perform a reset of the LTC3880.
This write-only command has no data bytes.
PMBus COMMAND DETAILS