MAX16064 Datasheet, PDF (34/52 Pages) Maxim Integrated Products – ±0.3% Accurate, Quad, Power-Supply Controller with Active-Voltage Output Control and PMBus Interface

±0.3% Accurate, Quad, Power-Supply Controller with
Active-Voltage Output Control and PMBus Interface
communicates with PMBus commands to retrieve the
fault/warning status information from the MAX16064.
The following status commands are supported:
STATUS_BYTE
STATUS_WORD
STATUS_VOUT
STATUS_TEMPERATURE
STATUS_CML
STATUS_MFR_SPECIFIC
MFR_STATUS_WORD
MFR_FAULT_REASON
MFR_FAULT_VOUT
MFR_FAULT_TEMP
See the individual command sections for more details.
Faults/warnings are cleared when any one of the follow-
ing conditions occurs:
• A CLEAR_FAULTS command is received.
• OPERATION commands are received that turn off and
on the power supplies or A3/CONTROL is toggled to
turn off and then turn on the power supplies.
• Bias power (AVDD, DVDD) to the MAX16064 is
removed and then reapplied.
The MAX16064 responds to fault conditions according
to the Manufacturer Fault Response command
(MFR_FAULT_RESPONSE). This command byte deter-
mines how the MAX16064 should respond to each par-
ticular fault. In addition, the MAX16064 responds to the
following error conditions.
1) If the internal reference fails to operate, SMBALERT
is asserted. To clear this fault, the MAX16064 must
go through a device reset.
2) The MAX16064 responds to unsupported com-
mands with a NACK.
3) When the host sends insufficient data (too few
bytes), the MAX16064 sets the CML bit and asserts
SMBALERT.
4) When the host sends too much data (too many
bytes), the MAX16064 sets the CML bit and asserts
SMBALERT.
When a read request is issued to a write-only com-
mand, the read operation is aborted and no warning is
issued.
PMBus Commands
A summary of the PMBus commands supported by the
MAX16064 is described in Table 4.
PAGE (00h)
The MAX16064 can control up to four power supplies
using one PMBus (I²C) address. Send the PAGE com-
mand with data 0 to 3 to select which power supply is
affected by all following commands. Set the PAGE to
255 when it is desired that following commands affect
all four power supplies. If, when PAGE = 255, the host
sends a command code that is not a global command
(any command in Table 4 that is not shaded), the
MAX16064 sets the CML, error flag. An example would
be to set the PAGE to 255 and then issue an OPERA-
TION command to turn on all the power supplies at
one time.
OPERATION (01h)
The OPERATION command is used to turn the power
supply on and off in conjunction with ENOUT_ according
to the ENOUT_ polarity select setup. The OPERATION
command is also used to cause the power supply to set
the output voltage to the upper or lower margin voltages.
The power supply stays in the commanded operating
mode until a subsequent OPERATION command or
change in the state of A3/CONTROL (if enabled)
instructs the power supply to change to another state.
The valid OPERATION command byte values are
shown in Table 5.
The OPERATION command controls how the MAX16064
responds when commanded to change the output. When
the command byte is 00h, the MAX16064 immediately
turns the power supply off and ignores any programmed
turn-off delay and fall time. When the command byte is
set to 40h, the MAX16064 powers down according to the
programmed turn-off delay and fall time.
In Table 5, Act On Fault means that if an output over-
voltage warning or output overvoltage fault is detected
when the output is margined high, the MAX16064 treats
this as a warning or fault and responds as programmed
by the warning limit or fault response command.
Similarly, if an output undervoltage warning or output
undervoltage fault is detected when the output is mar-
gined low, the MAX16064 treats this as a qualified
warning/fault event and responds as programmed by
the warning/fault limit or fault response command.
Any command value not shown in Table 5 is an invalid
command. If the MAX16064 receives a data byte that is
not listed in Table 5, then it may treat this as invalid
data, declares a communications fault (set CML bit and
assert SMBALERT), and responds as described in the
Fault Management and Reporting section.
The default OPERATION value is 00h.
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