Patent ID: 7798707

Claim:
A system comprising: first circuitry comprising: a first variable current source operable for driving a first current to a first node coupled to ground; and a second variable current source operable for driving a second current to a second node and a first resistor coupled in series to ground and in parallel to said first node, wherein said first current and said second current are selectable such that a first voltage measured at said first node and a second voltage measured at said second node are substantially equal; and second circuitry coupled to said first circuitry and comprising a third variable current source that is adjustable independently from said first and second variable current sources and is operable for driving a third current to a third node and a second resistor coupled in series to ground, wherein said third current is selectable such that a third voltage measured at said third node is substantially equal to a reference fourth voltage, and wherein measures of said second and third currents and measures of said first and second resistors are useful for determining a temperature value.