LTC7841 datasheet(42/48 Pages) AD

42 / 48 page

LTC7841

Rev. 0

For more information www.analog.com

MFR_CLEAR_PEAKS

The MFR_CLEAR_PEAKS command clears the MFR_*_

PEAK data values and restarts the peak monitor routine.

This write-only command requires no data bytes, but will

accept (and ignore) up to two.

STATUS_WORD

The STATUS_WORD command returns two bytes of infor-

mation 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_WORD also cause the ALERT

pin to be asserted.

Writing a “1” to a particular bit in the status word will

attempt to reset that fault in the status word and the

ALERT pin. If the fault is still present the status word bit

and ALERT will remain asserted. If the ALERT has previ-

ously been cleared by an ARA message, the ALERT will

be re-asserted. If the fault is no longer present, the ALERT

pin will be de-asserted and the fault bit in the status word

will be cleared.

All bits in the status word are also cleared by toggling

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

immediately be set again if the fault remains.

This command has two data bytes.

Table 7. Status Word Bit Descriptions and Conditions

BIT

DESCRIPTION

CONDITION

SET ALERT?

CLEARABLE BY

WRITING ‘1’ TO BIT?

0 (LSB)

None of the Above

If b[15] set due to VOUT undervoltage

Yes

Communication Failure

(See Note 1)

Yes

Temperature Fault

Temp > 150°C

Yes

VIN Undervoltage Fault

Not Implemented

Output Overcurrent Fault

Not Implemented

Output Overvoltage Fault

VOUT > PGOOD High Threshold

Yes

OFF

No Power to the Output (Note 2)

Busy

Not Implemented

Unknown

Not Implemented

Other

Not Implemented

Fans

Not Implemented

PGOOD

Inverted state of PGOOD pin

Manufacturer Specific

Not Implemented

Input Voltage/ Current/Power Fault

Not Implemented

Yes

Output Current/Power Fault

Not Implemented

15 (MSB)

Output Voltage Fault

VOUT outside PGOOD window

(Note 3)

Yes

Note 1: Communication failure is one of following faults: host sends too

few bits, host reads too few bits, host writes too few bytes, host reads too

many 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.

Note 2: Power may be off due to any one of the following conditions:

OPERATION ON cleared or power on initialization not complete. When

the power is off due to RUN low or due to a more serious fault conditions

such as VIN low or overtemperature fault, the PMBus interface is turned off

instead of asserting the OFF bit.

Note 3: This bit is disabled when drivers are off for any reason, soft-start

not complete, or the VOUT has not reached the PGOOD window for the first

time.

PMBus COMMAND DETAILS

LTC7841 Datasheet(PDF) 42 Page - Analog Devices

LTC7841 Datasheet(HTML) 42 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48

Datasheet Download

Link URL