Datasheet

MAX34451 PMBus 16-Channel V/I Monitor and
12-Channel Sequencer/Marginer
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MFR_TON_SEQ_MAX (E6h)
The MFR_TON_SEQ_MAX command sets an upper
limit, in milliseconds, from a sequencing group (either
SEQUENCE0orSEQUENCE1,aschosenbytheSEQ_
SELECTbitintheMFR_SEQ_CONFIGcommand),initi-
ating the power-up sequence until the channel expects
to begin its power-up based on an event, which could be
eitheralogiccombinationofpower-good (PG)andGPI
signals or a match on the SEQ pin, as configured with the
SELECTbitsin MFR_SEQ_CONFIG.The2 data bytes
areinDIRECTformat.Ifthisvalueiszero,thenthelimitis
disabled.InresponsetotheMFR_TON_SEQ_MAXbeing
exceeded,thedevicedoesthefollowing:
1) SetstheVOUTbitinSTATUS_WORD.
2) SetstheTON_MAX_FAULTbitinSTATUS_VOUT.
3) Responds as specified in the MFR_FAULT_
RESPONSE.
4) NotifiesthehostusingALERT assertion (if enabled in
MFR_MODE).
MFR_PWM_CONFIG (E7h)
TheMFR_PWM_CONFIGcommandisusedtoconfigure
theindividualPWMx/GPOy(x=0–7/y=12–19)outputs.
This command should not be changed while the power
supplies are being PWM margined. The MFR_PWM_
CONFIG command is described inTable37 and shown
inFigure13.
EachPWMn/GPOnpincanbeindependentlyconfigured
usingtheSELECT[2:0]bitstoperformoneofthefollowing:
● PWMmarginingoperation(SELECT[2:0]=000)
● Forcepinassertion(SELECT[2:0]=001)
● Forcepindeassertion(SELECT[2:0]=010)
● Assertwhenallenabledchannelpower-good(PG)or
GPIareasserted(SELECT[2:0]=011)
● Assert when any enabled alarm goes active
(SELECT[2:0]=100)
Also,eachPWMn/GPOnpincanbeindependentlyconfig-
ured to be active high or active low and either push-pull or
opendrainusingtheHI_LOandPP_ODbits,respectively.
IfSELECT[2:0]=011,thePWMn/GPOnoutputisconfig-
ured to assert when some combination of power-goods
(PGs) and GPIs from each channel are asserted. The
channels that should be used in this combination are
selected using the PG_GPI_SELECT bits 31:16. If the
PG_GPI_SELECT bit is cleared, then the associated
channel is not used in the logical combination to assert
theGPOoutput.IfthePG_GPI_SELECTbitisset,then
the PG or GPI from that channel isused in the logical
combinationtoasserttheGPOnoutput.Thisfunctionis
useful in creating system power-good signals.
IfSELECT[2:0]=100,thePWMn/GPOnoutputisconfig-
ured to assert when any of the enabled channel alarms
go active. The channel alarms are enabled with the
ALARM_SELECTbits31:16.IftheALARM_SELECTbit
is cleared, then the alarm from that channel is blocked.
If the ALARM_SELECT bit is set, then the alarm from
thatchannelisroutedtoanORfunction,suchthatany
enabledalarmassertstheGPOnoutput.Thealarmfunc-
tionischosenwiththeALARM_CONFIGbitsintheMFR_
FAULT_RESPONSEcommand.Thisfunctionisusefulfor
systemdebugorforenablingsystemstatusLEDs.