Patent ID: 6043687
Filing Date: 2000-03-28
Classification: H01L

Abstract:
A circuit that ensures precision matching between two or more resistive elements, comprising:a first resistive divider comprised of a first resistive element and a second resistive element that generates a first voltage, wherein the first resistive element and the second resistive element each have a first terminal, a second terminal, and a third terminal and are each characterized by a voltage coefficient;a comparison element that is provided with the first voltage generated by the first resistive divider and a second voltage, compares the first voltage to the second voltage, and generates an error signal indicative of a voltage difference between the first voltage and the second voltage;a feedback means coupled to the comparison element;wherein a first terminal difference of the first resistive element is controlled to be equal to a first terminal difference of the second resistive element and a second terminal difference of the first resistive element is controlled to be equal to a second terminal difference of the second resistive element, so that a ratio of the first resistive element to the second resistive element is a first predetermined value,wherein the first terminal difference of the first resistive element is defined as the difference in voltage between a voltage at the first terminal of the first resistive element and a voltage at the second terminal of the first resistive element, the first terminal difference of the second resistive element is defined as the difference in voltage between a voltage at the first terminal of the second resistive element and a voltage at the second terminal of the second resistive element, the second terminal difference of the first resistive element is defined as the difference in voltage between the voltage at the first terminal of the first resistive element and a voltage at the third terminal of the first resistive element, and the second terminal difference of the second resistive element is defined as the difference in voltage between the voltage at the first terminal of the first resistive element and a voltage at the third terminal of the second resistive element.