I'm testing a SN74LVC4245A for a circuit I'm designing where I need to pull roughly 24 mA from each 5V output. After looking over the DS a few times, I have not been able to find power dissipation ratings for this chip. Is there a set dissipation rating for this chip?
The spec is a littel vague - it is rated to 85C with all outputs at 24ma.
That being said, you can calculate what the part is disspating as a static load by taking (VCCa-VOHmin)*Iout for each pin.
For 4.5 and 5.5 Vcca the fdrop is specified at roughly 0.8V so 0.8V*24ma = 19.2mW per pin
For 8 pin 19.2mW*8= 153mW
The temperature rise of the package will be this mW* qJA (C/W) so for a DW package 153mW*46 C/W = 7 degree rise.