XC2287 / XC2286 / XC2285
XC2000 Family Derivatives
Preliminary
Package and Reliability
5.2
Thermal Considerations
When operating the XC228x in a system, the total heat generated on the chip must be
dissipated to the ambient environment to prevent overheating and resulting thermal
damages.
The maximum heat that can be dissipated depends on the package and its integration
into the target board. The “Thermal resistance RΘJA” is a measure for these parameters.
The power dissipation must be limited so the average junction temperature does not
exceed 150 °C.
The difference between junction temperature and ambient temperature is determined by
∆T = (PINT + PIOSTAT + PIODYN) × RΘJA
The internal power consumption is defined as
P
INT = VDDP × IDDP (see Table 14).
The static external power consumption caused by the output drivers is defined as
IOSTAT = Σ((VDDP-VOH) × IOH) + Σ(VOL × IOL)
P
The dynamic external power consumption caused by the output drivers (PIODYN) depends
on the capacitive load connected to the respective pins and the switching frequencies.
If the total power dissipation determined for a given system configuration exceeds the
defined limit countermeasures must be taken to ensure proper system operation:
•
•
•
•
Reduce VDDP, if possible in the system
Reduce the system frequency
Reduce the number of output pins
Reduce the load on active output drivers
Data Sheet
106
V0.91, 2007-02
Draft Version
INFINEON [ Infineon ]
