42.3.6 Thermal Characteristics

Table 42-6. 
Standard Operating Conditions (unless otherwise stated)
Param. No.Sym.CharacteristicTyp.UnitsConditions
TH01θJAThermal Resistance Junction to Ambient°C/W28-pin SPDIP package
°C/W28-pin SOIC package
°C/W28-pin SSOP package
°C/W28-pin VQFN 4x4 mm package
°C/W40-pin PDIP package
°C/W40-pin VQFN package
°C/W40-pin TQFP package
TH02TJMAXMaximum Junction Temperature150°C
TH03PDPower DissipationWPD = PINTERNAL+PI/O
TH04PINTERNALInternal Power DissipationWPINTERNAL = IDD x VDD(1)
TH05PI/OI/O Power DissipationWPI/O = Σ(IOL*VOL)+Σ(IOH*(VDD-VOH))
TH06PDERDerated PowerWPDER = PDMAX (TJ-TA)/θJA(2)
Note:
  1. IDD is current to run the chip alone without driving any load on the output pins.
  2. TA = Ambient Temperature, TJ = Junction Temperature.