44.3.6 Thermal Characteristics

Table 44-6. 
Standard Operating Conditions (unless otherwise stated)
Param No. Sym. Characteristic Typ. Units Conditions
TH01 θJA Thermal Resistance Junction to Ambient — °C/W 28-pin SPDIP package
— °C/W 28-pin SOIC package
— °C/W 28-pin SSOP package
— °C/W 28-pin VQFN 4x4 mm package
— °C/W 40-pin PDIP package
— °C/W 40-pin VQFN 5x5 mm package
— °C/W 44-pin TQFP 10x10 mm package
TH02 TJMAX Maximum Junction Temperature 150 °C
TH03 PD Power Dissipation — W PD = PINTERNAL+PI/O
TH04 PINTERNAL Internal Power Dissipation — W PINTERNAL = IDD x VDD(1)
TH05 PI/O I/O Power Dissipation — W PI/O = Σ(IOL*VOL)+Σ(IOH*(VDD-VOH))
TH06 PDER Derated Power — W PDER = 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.