Read DSP IC Embeded Source Code from protective memory which include flash and eeprom  ones, crack security fuse bit inside DSP IC chip and extract the firmware from DSP IC memory;

Read DSP IC Embeded Source Code from protective memory which include flash and eeprom ones, crack security fuse bit inside DSP IC chip and extract the firmware from DSP IC memory

We performed an experiment to estimate how much information could be extracted from the PIC16F84A chip after a normal erase operation was applied to it. As can be seen from Figure 46 the memory is completely erased and read as all 1’s well before the end of the standard 10 ms erase cycle. The threshold of the cell’s transistors becomes very low after the erase and cannot be measured the same way as with UV EPROM because the chip stops functioning if the power supply drops below 1.5 V.

With the power glitch technique, it is possible to reduce the supply voltage down to 1 V for a short period of time – enough for the information from memory to be read and latched into the internal buffer. But this is still not enough to shift the reference voltage of the sense amplifier low enough to detect the threshold of the erased cells.

Comments are closed.