MC56F8346 Freescale Semiconductor, Inc, MC56F8346 Datasheet - Page 165

• Manufacturer Part Number: MC56F8346
• Description: 56f8300 16-bit Digital Signal Controllers
• Manufacturer: Freescale Semiconductor, Inc

10.18 Power Consumption
This section provides additional detail which can be used to optimize power consumption for a given
application.
Power consumption is given by the following equation:
A, the internal [static component], is comprised of the DC bias currents for the oscillator, leakage current,
PLL, and voltage references. These sources operate independently of processor state or operating
frequency.
B, the internal [state-dependent component], reflects the supply current required by certain on-chip
resources only when those resources are in use. These include RAM, Flash memory and the ADCs.
C, the internal [dynamic component], is classic C*V
56800E core and standard cell logic.
D, the external [dynamic component], reflects power dissipated on-chip as a result of capacitive loading
on the external pins of the chip. This is also commonly described as C*V
of the IO cell types used on the device reveal that the power-versus-load curve does have a non-zero
Y-intercept.
Power due to capacitive loading on output pins is (first order) a function of the capacitive load and
frequency at which the outputs change.
in the IO cells as a function of capacitive load. In these cases:
TotalPower = Σ((Intercept +Slope*Cload)*frequency/10MHz)
where:
Freescale Semiconductor
Preliminary
Total power =
•
•
Summation is performed over all output pins with capacitive loads
TotalPower is expressed in mW
+D: external [dynamic component]
+B: internal [state-dependent component]
+C: internal [dynamic component]
+E: external [static]
A: internal [static component]
Table 10-25 IO Loading Coefficients at 10MHz
PDU08DGZ_ME
PDU04DGZ_ME
56F8346 Technical Data, Rev. 15
Table 10-25
provides coefficients for calculating power dissipated
2
Intercept
1.15mW
*F CMOS power dissipation corresponding to the
1.3
0.11mW / pF
0.11mW / pF
Slope
2
*F, although simulations on two
Power Consumption
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