ltc2978 Linear Technology Corporation, ltc2978 Datasheet - Page 31

• Manufacturer Part Number: ltc2978
• Description: Octal Pmbus Power Supply Monitor And Controller With Eeprom
• Manufacturer: Linear Technology Corporation

STATUS_BYTE:
The STATUS_BYTE command returns the summary of the
most critical faults or warnings which have occurred, as
shown in the following table:
STATUS_BYTE Data Contents
STATUS_WORD:
The STATUS_WORD command returns two bytes of infor-
mation with a summary of the unit’s fault condition. Based
on the information in these bytes, the host can get more
information by reading the appropriate status byte.
The low byte of the STATUS_WORD is the same register
as the STATUS_BYTE command.
operaTion
BIT(S) SYMBOL
b[7]
b[6]
b[5]
b[4]
b[3]
b[2]
b[1]
b[0]
Status_byte_busy
Status_byte_off
Status_byte_vout_ov
Status_byte_iout_oc
Status_byte_vin_uv
Status_byte_temp
Status_byte_cml
Status_byte_high_byte Fault/warning not listed in b[7:1].
OPERATION
Device busy when PMBus command
received.
This bit is asserted if the unit is
not providing power to the output,
regardless of the reason, including
simply not being enabled.
An output overvoltage fault has
occurred.
Not supported. Always returns 0.
A V
A temperature fault or warning has
occurred.
A communication, memory or logic
fault has occurred.
IN
undervoltage fault has occurred.
STATUS_WORD Data Contents
BIT(S) SYMBOL
b[15] Status_word_vout
b[14] Status_word_iout
b[13] Status_word_input
b[12] Status_word_mfr
b[11] Status_word_power_not_good The POWER_GOOD signal, if
b[10] Status_word_cooling
b[9]
b[8]
b[7]
b[6]
b[5]
b[4]
b[3]
b[2]
b[1]
b[0]
Status_word_other
Status_word_unknown
Status_word_busy
Status_word_off
Status_word_vout_ov
Status_word_iout_oc
Status_word_vin_uv
Status_word_temp
Status_word_cml
Status_word_high_byte
OPERATION
An output voltage fault or
warning has occurred.
Not supported. Always returns 0.
An input voltage fault or
warning has occurred.
A manufacturer specific fault
has occurred.
present is negated. Power is
not good.
Not supported. Always returns 0.
Not supported. Always returns 0.
Not supported. Always returns 0.
Device busy when PMBus
command received.
Status_byte_off
Status_byte_vout_ov
Not supported. Always returns 0.
Status_byte_vin_uv
Status_byte_temp
Status_byte_cml
A bit in the high byte of the
STATUS_WORD (b[15:8]) is
set.
LTC2978

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