PMBus 6-Channel Power-Supply Manager

26

STORE_DEFAULT_ALL (11h)

The STORE_DEFAULT_ALL command instructs the device to transfer the device configuration information to the internal

flash memory array. Not all information is stored. Only configuration data is stored, not any status, or operational data.

If an error occurs during the transfer, ALERT asserts if enabled and the CML bit in STATUS_BYTE and STATUS_WORD

is set to 1. No bits are set in STATUS_CML. It is NOT recommended to use the STORE_DEFAULT_ALL command

while the device is operating power supplies. The device is unresponsive to PMBus commands and does not

monitor power supplies while transferring the configuration. This command is write-only. There is no data byte for this

command.

RESTORE_DEFAULT_ALL (12h)

The RESTORE_DEFAULT_ALL command transfers the default configuration information from the internal flash memory

array to the user memory registers in the device. The RESTORE_DEFAULT_ALL command should only be executed

when the device is not operating the power supplies. Upon a device reset, this command is automatically executed

by the device without PMBus action required. This command is write-only. There is no data byte for this command.

CAPABILITY (19h)

The CAPABILITY command is used to determine some key capabilities of the device. The CAPABILITY command is

read-only. The message content is described in the Table 12.

VOUT_MODE (20h)

The VOUT_MODE command is used to report the data format of the device. The device uses the DIRECT format for all

the voltage-related commands. The value returned is 40h, indicating DIRECT data format. This command is read-only.

If a host attempts to write this command, the CML status bit is asserted. See Table 3 for the m, b, and R values for the

various commands.

VOUT_MARGIN_HIGH (25h)

The VOUT_MARGIN_HIGH command loads the device with the voltage to which the power-supply output is to be

changed when the OPERATION command is set to margin high. If the power supply is already operating at margin

high, changing VOUT_MARGIN_HIGH has no effect on the output voltage. The device only adjusts the power supply to

the new VOUT_MARGIN_HIGH voltage after receiving a new margin high OPERATION command. The 2 data bytes are

in DIRECT format. If the device cannot successfully close-loop margin the power supply, the device keeps attempting

to margin the supply and does the following:

1) Sets the NONE OF THE ABOVE bit in STATUS_BYTE.

2) Sets the NONE OF THE ABOVE and MFR bits in STATUS_WORD.

3) Sets the MARGIN_FAULT bit in STATUS_MFR_SPECIFIC.

4) Notifies the host through ALERT assertion (if enabled in MFR_MODE).

Table 12. CAPABILITY Command Byte

BIT

DESCRIPTION

MEANING

7

Packet-Error Checking

0 = PEC not supported.

6:5

PMBus Speed

00 = Maximum supported bus speed is 100kHz.

4

ALERT

1 = Device supports an ALERT output (if ALERT is enabled in MFR_MODE).

0 = Device does not support ALERT output (ALERT is disabled in MFR_MODE).

3:0

Reserved

Always returns 0000.