Patent ID: 7733337
Filing Date: 2010-06-08
Classification: G09G,H03F

Abstract:
1. An amplification circuit, comprising: an input to which an input voltage is provided, a capacitor arrangement, and a switching arrangement; wherein: the capacitor arrangement includes: a first capacitor that is configured as a voltage-dependent capacitor having a first voltage-dependent capacitance, and a second capacitor, coupled to the first capacitor, that is configured as a voltage-dependent capacitor having a second voltage-dependent capacitance; the circuit is operable in two modes, a first mode in which the input voltage is provided to an input terminal of at least the first capacitor, and a second mode in which the switching arrangement causes charge to be redistributed between the first and second capacitors; and the switching arrangement is configured to receive a first gain-control signal that is arranged to change the capacitance of the first capacitor and a second gain-control signal that is arranged to change the capacitance of the second capacitor; and wherein the switching arrangement includes an input switch for selectively coupling the input voltage to the capacitor arrangement, and wherein in the first mode, the input switch couples the input voltage to the capacitor arrangement, and in the second mode, the input switch isolates the input voltage from the capacitor arrangement; and wherein in the second mode, at least one of the first and second gain-control signals change a voltage on a gain-control terminal of the first and/or second capacitor.