Elmer,
So using Ohms law, 28.2A*1.7V= 47.94 or 48 Watts yet AMD claims only 43 Watts @1.6v in their power dissipation section.
First off - this is not Ohms Law. Ohm's law is about the relationship among the three fundamental electrical entities - Voltage, Current and resistance. Power = V*I is just an equation for power which in turn comes from the basic definitions of units Volt and Ampere . Applying Ohms law (I=V/R) and the power equation(P=VxI), you can deduce other equations for power = V^2/R or I^2*R in terms of "R",
Anyways, this is a very valid equation, and it doesn't make any difference for the main point you are trying to make here - the Athlons max power spec is shown to be different from the Max power based on Vcc and Iccmax of the chip.
To make this discussion simple, lets assume the Vcc and Icc max values you are looking at are DC values. In this case, Vcc * Icc for sure gives you the power supplied by the power supply. Now does it equal to the power dissipated on the chip? The answer would be - it depends.
Let's also assume we have a device with one output pin. The conditions are Vcc = 5V, Icc=10Amps while the output is at high - say 2.4V - sourcing 5Amps into a load. From this we can say that the power supply is supplying 50Watts to the chip, but the chip is dissipating only 38 Watts while the load is consuming 12 Watts. In other words, if a chip has I/O lines, then you can't say conclusively that the power dissipated by that chip equals Vcc*Icc.
Regards,
Goutama |
