Multi-sampled, charge-sharing thermometer in memory device

A system comprising:

• one or more memory dice;
• a diode having a threshold voltage that changes with temperature;
• an analog-to-digital converter (ADC) coupled with the one or more memory dice, the ADC comprising:
• a voltage comparator having a positive terminal coupled with the diode;
• a first capacitor coupled between a negative terminal of the voltage comparator and ground;
• a first switch coupled with the first capacitor;
• a second switch coupled between the first switch and a voltage reference node;
• and
• a second capacitor connected between the first switch and the second switch, the second capacitor also coupled with the ground;
• a pulse generator coupled with the ADC, the pulse generator to generate pulses that are to close the first switch, causing the first capacitor and the second capacitor to equalize charge;
• and
• an inverter coupled between the pulse generator and the second switch, the inverter to output an inverted signal that is to close the second switch, causing the second capacitor to be pre-charged via the voltage reference node.

A method of operating a memory device comprising a memory array, a diode having a threshold voltage that changes with temperature, and an analog-to-digital converter (ADC) coupled with the memory array, the ADC comprising a voltage comparator having a positive terminal coupled with the diode, a first capacitor coupled between a negative terminal of the voltage comparator and ground, and a second capacitor coupled between the first capacitor and a voltage reference node, the second capacitor also coupled with the ground and having a smaller capacitance than that of the first capacitor, and wherein the method of operating the memory device comprises:

• directing a pulse generator to generate pulses, wherein the pulses are to cause the first capacitor to connect to the second capacitor and equalize charge between the first capacitor and the second capacitor;
• generating, from the pulses, an inverted signal that is to cause the second capacitor to be coupled with the voltage reference node to precharge the first capacitor before equalization of the charge between the first capacitor and the second capacitor;
• and
• tracking a number of one values output by the voltage comparator to determine a temperature value of the diode.