Patent ID: 6215291
Filing Date: 2001-04-10
Classification: H02J

Abstract:
A reference voltage circuit, comprising:a current mirror coupled to a first power supply;a first transistor having a first current handling terminal coupled to said current mirror, a second current handling terminal providing a first current, and a control terminal coupled to a first bias source;a second transistor having a first current handling terminal coupled to said current mirror, a second current handling terminal providing a second current, and a control terminal coupled to said first bias source;a differential pair having a first input terminal coupled to receive said first current, a second input terminal coupled to receive said second current, a first and second output terminals providing a first output voltage, said first output voltage having a value indicative of a difference between said first current and said second current;a bandgap reference circuit coupled to receive said first output voltage of said differential pair and generating a first reference voltage at an output terminal anda third transistor having a first current handling terminal coupled to said first power supply, a second current handling terminal coupled to said output terminal of said bandgap reference circuit, and a control terminal coupled to said first current handling terminal of said second transistor;wherein said first reference voltage varies in relation to said first power supply.