LTC7106

17

Rev A

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STATUS_BYTE

TheSTATUS_BYTEcommandreturnsonebyteofinforma-

tion with a summary of the unit’s fault condition.

See Table 7 for a list of the status bits that are supported

and the conditions in which each bit is set. Certain bits

when set in the STATUS_BYTE also cause the ALERT pin

to be asserted.

Writinga“1”toaparticularbitinthestatusbytewillattempt

to reset that fault in the status byte and the ALERT pin. If

PMBus COMMAND DETAILS

the fault is still present the status byte bit and ALERT will

remain asserted. If the ALERT has previously been cleared

by an ARA message, the ALERT will be re-asserted. If the

faultisnolongerpresent,theALERTpinwillbede-asserted

and the fault bit in the status byte will be cleared.

All bits in the status byte are also cleared by toggling the

RUN_MSTR pin or the ON bit in OPERATION. The bit will

immediately be set again if the fault remains.

Table 7. Status Byte Bit Descriptions and Conditions

BIT

DESCRIPTION

CONDITION

SET ALERT?

CLEARABLE BY

WRITING ‘1’ TO BIT?

0 (LSB)

None of the Above

MFR_VOUT_MAX Register Exceeded

No

Yes

1

Communication Failure

(See Note 1)

Yes

Yes

2

Temperature Fault

Not Implemented

3

Not Implemented

4

Output Overcurrent Fault

Not Implemented

5

Output Overvoltage Fault

Not Implemented

6

OFF

Not Implemented

7

Busy

Not Implemented

Note 1: Communication failure is one of following faults: host sends too few bits, host reads too few bits, host writes too few bytes, improper R/W bit

set, unsupported command code, attempt to write to a read-only command. See PMBus Specification v1.2, Part II, Sections 10.8 and 10.9 for more

information.