Rainbow Electronics MAX34441 - Manual (Page 34)

PMBus 5-Channel Power-Supply Manager
and Intelligent Fan Controller
MAX34441
34
OT_WARN_LIMIT (51h)
The OT_WARN_LIMIT command sets the temperature, in degrees Celsius, of the selected temperature sensor at which
an overtemperature warning is detected. The 2 data bytes are in DIRECT format. In response to the OT_WARN_LIMIT
being exceeded, the device does the following:
1) Sets the TEMPERATURE bit in STATUS_BYTE.
2) Sets the TEMPERATURE and MFR bits in STATUS_WORD.
3) Sets the OT_WARN bit in STATUS_MFR_SPECIFIC.
4) Notifies the host through ALERT assertion (if enabled in MFR_MODE).
POWER_GOOD_ON (5Eh)
The POWER_GOOD_ON command sets the value of the output voltage that causes the PG output (if enabled in
MFR_MODE) to assert. All enabled power supplies must be above their associated POWER_GOOD_ON thresholds
before the PG output is asserted. All the enabled power supplies must also be above POWER_GOOD_ON for power-
supply margining to begin. The POWER_GOOD_ON level is normally set higher than the POWER_GOOD_OFF level
and VOUT_UV_FAULT_LIMIT. The 2 data bytes are in DIRECT format.
POWER_GOOD_OFF (5Fh)
The POWER_GOOD_OFF command sets the value of the output voltage that causes the PG output (if enabled in
MFR_MODE) to deassert after it has been asserted. Any enabled power supply that falls below the associated
POWER_GOOD_OFF threshold causes the PG output to be deasserted. The POWER_GOOD_OFF level is normally set
lower than the POWER_GOOD_ON level. The 2 data bytes are in DIRECT format.
The POWER_GOOD# bits in STATUS_WORD and STATUS_MFR_SPECIFIC are set when the VOUT level of a power
supply falls from greater than POWER_GOOD_ON to less than POWER_GOOD_OFF.
Figure 4. Power-Supply Sequencing
TON_DELAY
OPERATION
COMMAND CODE OR
CONTROL PIN
PSEN PIN
(ACTIVE HIGH OR LOW/
OPEN DRAIN OR PUSH-PULL)
ADC INPUT
POWER_GOOD# BIT IN
STATUS_MFR_SPECIFIC
TON_MAX_FAULT_LIMIT
VOUT_UV_FAULT_LIMIT
TOFF_DELAY
POWER_GOOD_OFF
POWER_GOOD_ON