SMD Voltage Regulator 662k very hot, how to repair it?
From the picture I guess it is a roboduino. The only voltage regulator is the 662k, it is too small compared to other voltage regulators!!! (have a look at the size and sink of the official arduino), so it is normal that the temperature is high. (arduino uno can get up to 1A and the regulator is bigger)

To reduce temperature just use the lowest input source (for instance, for arduino 5 volts, use 7 volts source, not 12 volts source). The bigger input voltage, the higher temperature in the regulator.

Solutions.


replace the 662K with another 662K one.
use a bigger voltage regulator. Since 66K space is tight (SOT-23) and no sink space I suggest to solder a TO-92 like voltage regulator. Not nice solution, but handy.