Datasheet

MAX34451 PMBus 16-Channel V/I Monitor and
12-Channel Sequencer/Marginer
www.maximintegrated.com
Maxim Integrated │ 21
Table 5. PMBus Command Code Coefficients
Table 6. Coefficients for DIRECT
Format Value
Sending a DIRECT Format Value
To send a value, the host must use the following equation
tosolveforY:
Y=(mX+b)x10
R
where Y is the 2-byte, two’s complement integer to be
senttotheunit;mistheslopecoefficient;Xisthereal-
world value, in units such as volts, to be converted for
transmission;bistheoffset;andRistheexponent.
The following example demonstrates how the host can
send and retrieve values from the device. Table 6 lists the
coefficients used in the following parameters.
If a host wants to set the device to change the power-
supplyoutputvoltageto3.465V(or3465mV),thecorre-
spondingVOUT_MARGIN_HIGHvalueis:
Y=(1x3465+0)x10
0
=3465(decimal)
=0D89h(hex)
PARAMETER COMMANDS UNITS RESOLUTION MAXIMUM m b R
Voltage
VOUT_MARGIN_HIGH
VOUT_MARGIN_LOW
VOUT_OV_FAULT_LIMIT
VOUT_OV_WARN_LIMIT
VOUT_UV_WARN_LIMIT
VOUT_UV_FAULT_LIMIT
POWER_GOOD_ON
POWER_GOOD_OFF
READ_VOUT
MFR_VOUT_PEAK
MFR_VOUT_MIN
mV 1 32767 1 0 0
VoltageScaling VOUT_SCALE_MONITOR — 1/32767 1 32767 0 0
Current
IOUT_OC_FAULT_LIMIT
IOUT_OC_WARN_LIMIT
READ_IOUT
MFR_IOUT_PEAK
MFR_IOUT_AVG
A 0.01 327.67 1 0 2
CurrentScaling IOUT_CAL_GAIN mΩ 0.1 3276.7 1 0 1
Temperature
OT_FAULT_LIMIT
OT_WARN_LIMIT
READ_TEMPERATURE_1
MFR_TEMPERATURE_PEAK
°C 0.01 327.67 1 0 2
Timing
TON_DELAY
TON_MAX_FAULT_LIMIT
TOFF_DELAY
MFR_FAULT_RETRY
MFR_TON_SEQ_MAX
ms 0.2 6553.4 5 0 0
COMMAND
CODE
COMMAND NAME m b R
25h VOUT_MARGIN_HIGH 1 0 0
8Bh READ_VOUT 1 0 0