Extract MCU data normally will take more than three experiments to get success. We can test how much data can be read directly from MCU after restoration. After the standard 10 microsecond wipe out cycle, memorizer can be wiped out completely. And all the read out information are “1”. After elimination and erase of data inside the MCU, the threshold value of transistors could be low. And we can’t use the UV EPROM method to test it after extract MCU because the MCU won’t operate if the power supply voltage lower than 1.5V. use power supply noise technology can shortly decrease the power supply voltage to 1V. refers to threshold voltage which can be read and extract from MCU memorizer to locked internal buffer is sufficient enough.

But it still not enough to change the sensitive amplifier reference voltage to low level after extract MCU, and test the threshold voltage from erased unit of MCU. In order to get the result, we need to some other tricks on the power glitch of MCU extraction. All the floating grid transistors’ threshold value in the memorizer grid can be altered temporarily after MCU extraction which makes is possible to measure the threshold value of already erased unit close to 0, through the precise management and control of memorizer erase operation, makes the bottom and control grid can be pre-charged when extract MCU and terminate the operation when the occurrence of tunnel effect.

Consequently, excessive ions being left on the bottom of floating gate and change the threshold value of transistor after extract MCU. Captured excessive ions can combine with each other around 1 second and it is enough to read the whole memorizer of MCU after extract. In order to evaluate the threshold voltage value in each transistor, can use the different voltages combination with power glitch to repeat this process.