Chadwick's Control Chip wass a mind control device that was inserted into the brain of Chadwick Jones. It manipulated his emotions and memories until its destruction in 2014.
The chip was designed to suppress Chadwick's memories about his early past. Anything before he turned eight years old is a complete mystery to him and he does not remember if he has any family members. It also instantaneously wiped his short term memory if somebody mentioned the existence of the chip in his presence. Along with memory manipulation, the chip also kept him emotionally docile, making it so he will not become angry or attempt to defend himself, even when his life is being threatened by someone like The Meddler.
However, the chip was not perfect. If something got Chadwick emotional enough, the chip would fail to suppress him and damage itself in the process. When the chip became damaged a significant amount it began to make visible blue sparks whenever it wiped Chadwick's memory. A raw release of emotion such as Chadwick's transformation into a Super Saiyan was enough to disintegrate it.
The chip was inserted into Chadwick's brain by Panther in order to prevent him from becoming a Super Saiyan. Luckily, Chadwick managed to accidentally escape to New Zealand, where he was found by the PRU, a resistance group that knew about the existence of the chip. Chadwick could not be informed about the chip directly, so Don Maccaroni, the leader of the New Zealand outpost, came up with a plan to frustrate him into breaking the chip by forcing him to watch bad movies. By doing this, he managed to enrage Chadwick into a frenzy, but it only managed to damage the chip instead of breaking it. So instead, Chadwick was told to begin a retrospective on the Dragon Ball franchise, which would hopefully break the chip before Panther can track him down. By the end of the retrospective, the control chip was still hanging on by a thread. As a last resort, Don tells Chadwick that he needs to become a super saiyan in order to destroy it once and for all. In order for that to happen, Don orders him to review Dragonball Evolution. At the prospect of this, Chadwick flies into a rage, causing such an emotional release that he transforms into a super saiyan, utterly destroying the chip and freeing his mind.