FOOD ITEM SCALES, METHODS FOR CALIBRATING SAME, AND METHODS FOR DETERMINING THE WEIGHT OF FOOD ITEMS

1 . A method for calibrating a food item scale, the method comprising:

detecting a food item weight transition from a first weight to a second weight;

determining, when the food item weight transition is positive, if the second weight is greater than a full weight threshold value; and

setting a full weight value as equal to the second weight when the second weight is greater than the full weight threshold value.

2 . The method of claim 1 , wherein the full weight threshold value is between 90% and 98% of the full weight value.

3 . The method of claim 1 , wherein the full weight threshold value is between 94% and 98% of the full weight value.

4 . The method of claim 1 , further comprising determining if the food item weight transition exceeds a transition threshold, and wherein the determining step only occurs when the food item weight transition exceeds the transition threshold.

5 . The method of claim 1 , further comprising:

determining, when the food item weight transition is negative, if the second weight is less than an empty weight threshold value; and

setting an empty weight value as equal to the second weight value when the second weight is less than the empty weight threshold value.

6 . The method of claim 5 , wherein the empty weight threshold value is between 102% and 110% of the empty weight value.

7 . The method of claim 5 , wherein the empty weight threshold value is between 102% and 106% of the empty weight value.

8 . A method for determining a weight of a food item, the method comprising:

receiving a voltage signal and a sine wave generator signal;

capturing a first voltage signal value at a first trigger datum and a second voltage signal value at a second trigger datum; and

determining the weight based on the first voltage signal value and the second voltage signal value.

9 . The method of claim 8 , wherein the first trigger datum is a first time at which the sine wave generator signal crosses zero voltage and the second trigger datum is a second time at which the voltage signal is at a maximum value.

10 . The method of claim 8 , wherein the voltage signal and the sine wave generator signal each have a sine wave pattern.

11 . The method of claim 8 , wherein the determining step comprises:

determining a gain value and a phase lag value based on the first voltage signal value and the second voltage signal value; and

determining the weight based on the gain value and the phase lag value.

12 . The method of claim 8 , further comprising transmitting the weight to an independent storage device.

13 . A food item scale, comprising:

a force sensitive resistor;

a signal conditioning circuit connected to the force sensitive resistor; and

a controller, the controller configured for:

receiving a voltage signal and a sine wave generator signal from the signal conditioning circuit;

capturing a first voltage signal value at a first trigger datum and a second voltage signal value at a second trigger datum; and

determining a weight of the food item based on the first voltage signal value and the second voltage signal value.

14 . The food item scale of claim 13 , wherein the first trigger datum is a first time at which the sine wave generator signal crosses zero voltage and the second trigger datum is a second time at which the voltage signal is at a maximum value.

15 . The food item scale of claim 13 , wherein the voltage signal and the sine wave generator signal each have a sine wave pattern.

16 . The food item scale of claim 13 , wherein the determining step comprises:

determining a gain value and a phase lag value based on the first voltage signal value and the second voltage signal value; and

determining the weight based on the gain value and the phase lag value.

17 . The food item scale of claim 13 , wherein the controller comprises an analog-to-digital converter.

18 . The food item scale of claim 13 , wherein the food item scale further comprises a housing, the force sensitive resistor and signal conditioning circuit disposed within the housing.