Patent ID: 7928721
Filing Date: 2011-04-19
Classification: G01R

Abstract:
1. An amplifier circuit, comprising: a first test terminal; a second test terminal; a first output terminal; a second output terminal coupled to a first fixed voltage; and an output voltage generator having a first input coupled to the first test terminal, a second input coupled to a second fixed voltage, and an output coupled to the second test terminal and the first output terminal, the output voltage generator being operable to apply to the first output terminal a voltage having a magnitude determined by the voltage applied to the first input of the output voltage generator referenced to the second fixed voltage, the output voltage generator comprising a negative integrating driver circuit having a first input coupled to the first test terminal, a second input coupled to the second fixed voltage, and an output coupled to the second test terminal and the first output terminal, the negative integrating driver circuit being operable to negatively integrate a voltage applied to the first test terminal referenced to the second fixed voltage, the negative integrating driver circuit comprising: an amplifier having a gain, the amplifier having a first input coupled to the first test terminal, an output, and a second input coupled to the output; and an integrator having an inverting input coupled to the output of the amplifier and an output coupled to the first output terminal and the second input terminal, the integrator being operable to integrate a voltage received from the output of the amplifier to provide an output voltage to the first output terminal and the second input terminal, the integrator comprising: