LTC2977 datasheet(101/138 Pages) AD

101 / 138 page

LTM4664A

101

Rev. 0

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PMBus COMMAND DETAILS

VOUT_MARGIN_HIGH

The VOUT_MARGIN_HIGH command loads the unit with the voltage to which the output is to be changed, in Volts,

when the OPERATION command is set to “Margin High”. The value should be greater than VOUT_COMMAND. The

maximum guaranteed value on VOUT_MARGIN_HIGH is 3.6V.

This command will not be acted on during TON_RISE and TOFF_FALL output sequencing. The VOUT_TRANSITION_

RATE will be used if this command is modified while the output is active and in a steady-state condition.

This command has two data bytes and is formatted in Linear_16u format.

VOUT_COMMAND

The VOUT_COMMAND consists of two bytes and is used to set the output voltage, in volts. The maximum guaranteed

value on VOUT is 3.6V.

This command will not be acted on during TON_RISE and TOFF_FALL output sequencing. The VOUT_TRANSITION_

RATE will be used if this command is modified while the output is active and in a steady-state condition.

This command has two data bytes and is formatted in Linear_16u format.

VOUT_MARGIN_LOW

The VOUT_MARGIN_LOW command loads the unit with the voltage to which the output is to be changed, in volts,

when the OPERATION command is set to “Margin Low”. The value must be less than VOUT_COMMAND.

This command will not be acted on during TON_RISE and TOFF_FALL output sequencing. The VOUT_TRANSITION_

RATE will be used if this command is modified while the output is active and in a steady-state condition.

This command has two data bytes and is formatted in Linear_16u format.

VOUT_UV_WARN_LIMIT

The VOUT_UV_ WARN_LIMIT command reads the value of the output voltage measured by the ADC at the sense pins,

in volts, which causes an output voltage low warning.

In response to the VOUT_UV_WARN_LIMIT being exceeded, the device:

• Sets the NONE_OF_THE_ABOVE bit in the STATUS_BYTE

• Sets the VOUT bit in the STATUS_WORD

• Sets the VOUT Undervoltage Warning bit in the STATUS_VOUT command

• Notifies the host by asserting ALERT pin, unless masked

This command has two data bytes and is formatted in Linear_16u format.

VOUT_UV_FAULT_LIMIT

The VOUT_UV_FAULT_LIMIT command reads the value of the output voltage measured by the UV supervisor com-

parator at the sense pins, in volts, which causes an output undervoltage fault.

This command has two data bytes and is formatted in Linear_16u format.

LTC2977 Datasheet(PDF) 101 Page - Analog Devices