Any suggestions? about others ICs than TIP120. I want to use with power supply 12 V 2 A to power up the heat-cooling Peltier up to 65 degree C.
Well, the TIP120 is essentially obsolete, and drops 1 V and therefore dissipates 2 Watts at 2 Amps, so you would certainly need a heatsink.
Nowadays, use a logic-level FET such as an AOD4184 which turns on hard at 4.5 V, dissipating only 40 mW at 2 Amps so needing no heatsink.
Cheaply available on eBay as a ready-assembled module with opto-isolation.
Thanks a lot.