Abstract: Despite the harshness of the space radiation on satellite electronic components, some Commercial Of The Shelf (COTS) can sustain such harsh environment. Thus, the low-cost advantage of the COTS can be utilized given that these electronic components meet the technical design requirements of the targeted satellite subsystem. Because of the complexity of microcontrollers and their various integrated functionality, they present a hardness assurance challenge. A careful technique was followed in analyzing the space radiation effects. Then rigorous tests should be conducted to test the performance of the candidate microcontrollers under these effects. This paper presents the predicted dose depth curve and the total ionizing does test results for a commercial ARM microcontroller for Low Earth Orbit (LEO) satellites. Such test results help estimate the effect of space environment on the microcontroller and decide if such microcontroller is an accepted candidate for LEO missions or not.