Analog-to-digital conversion method and device, in high-density multilevel non-volatile memory devices

An analog-to-digital conversion device incorporated in a high-density multilevel non-volatile memory device that includes a multilevel memory cell having a floating gate transistor with gate, drain, and source terminals, the device comprising:

• a plurality of voltage comparators, each having a first input coupled to the gate terminal, a second input maintained at a corresponding reference voltage value, and an output, each voltage comparator being a time continual comparator;
• a logic block connected to the outputs of the voltage comparators and structured to extract most significant bits of the memory cell;
• and
• means for initiating analog-to-digital conversion of an analog voltage of the memory cell during a read transient phase.

An analog-to-digital conversion device incorporated in a high-density multilevel non-volatile memory device that includes a multilevel memory cell having a floating gate transistor with gate, drain, and source terminals, the device comprising:

• a plurality of voltage comparators, each having a first input coupled to the gate terminal, a second input maintained at a corresponding reference voltage value, and an output, each voltage comparator being a time continual comparator;
• a first logic block connected to the outputs of the voltage comparators and structured to extract most significant bits of the memory cell;
• and
• a selection block, connected downstream of the first logic block, effective to select additional reference voltage values for application to corresponding additional comparators provided for a subsequent second conversion step in order to extract least significant bits of the memory cell by means of another logic block being connected to outputs of the additional comparators.