Maximum current rating requires even
load distribution across I/O pins. Maximum current rating may be limited by the
device package power dissipation characterizations, see “Thermal
Characteristics” to calculate device specifications.
Power dissipation is calculated as
follows:
PDIS = VDD x {IDD - Σ IOH} + Σ
{(VDD - VOH) x IOH} + Σ (VOI x
IOL)
Internal Power Dissipation is
calculated as follows:
PINTERNAL = IDD x VDD
where IDD is current to run the chip alone without
driving any load on the output pins.
I/O Power Dissipation is calculated
as follows:
PI/O
=Σ(IOL*VOL)+Σ(IOH*(VDD-VOH))
Derated Power is calculated as
follows:
PDER =
PDMAX(TJ-TA)/θJA
where TA=Ambient Temperature, TJ = Junction
Temperature.
† NOTICE: Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device. This is a stress rating
only and functional operation of the device at those or any other conditions above those
indicated in the operation listings of this specification is not implied. Exposure above
maximum rating conditions for extended periods may affect device reliability.