Datasheet

Data Sheet ADM1276
Rev. C | Page 31 of 48
format values must be divided by 256 prior to being
converted with the coefficients shown in Tabl e 7.
Example 3: The PIN_OP_WARN_LIMIT command requires a
power limit value expressed in direct format.
If the required power limit is 350 W and the sense resistor is
1 mΩ, the first step is to determine the m coefficient. Assuming
the 0 V to 20 V range, m = 6043 × 1, which is 6043.
Using Equation 1, and working with the 0 V to 20 V range,
Y = ((6043 × 350) × 10
-2
Y = 21,150.5 = 21,151 (rounded up to integer form)
Writing a value of 21,151 with the PIN_OP_WARN_LIMIT
command sets an overpower warning at 350 W.
Table 7. PMBus Conversion to Real-World Coefficients
Coefficient Current (A)
Voltage (V) Power (W)
0 V to 6 V Range 0 V to 20 V Range 0 V to 6 V Range 0 V to 20 V Range
m 807 × R
SENSE
6720 19,199 2115 × R
SENSE
6043 × R
SENSE
b 20,475 0 0 0 0
R −1 −1 −2 −1 −2