Patent ID: 7579860

Claim:
A method for producing a reference signal, the method comprising the steps of: supplying a first current to a diode; sampling a first voltage across the diode to produce a first digital value, V BE (I1x), wherein the first voltage is based on the first current; supplying a second current to the diode, wherein the first current and the second current have different current densities; sampling a second voltage across the diode to produce a second digital value, V BE (Inx), wherein the second voltage is based on the second current; computing a bandgap voltage, V k , of the diode from the first digital value and the second digital value as V K =V BE ( I 1 x )+ G [V BE ( Inx )−V BE ( I 1 x )], wherein G is a fixed gain; determining a digital reference value, K, as a ratio of the bandgap voltage and a reference voltage; and converting the digital reference value to an analog voltage for use in producing the reference signal.