Patent ID: 7092538
Filing Date: 2006-08-15
Classification: H03F

Abstract:
1. An input buffer circuit for a microphone, the circuit comprising: an input; an input transistor operably connected to the input; a first switching signal; a second switching signal; a first set of switches comprising a first, second, and third switch, each switch of the first set of switches having an “on” state and an “off” state, each switch of the first set of switches being responsive to the first switching signal; a second set of switches comprising a first, second, and third switch; each switch of the second set of switches having an “on” state and an “off” state, each switch of the second set of switches being responsive to the second switching signal, the first and second sets of switches composing a complementary set of switches wherein the “on” state of the first set of switches does not overlap with the “on” state of the second set of switches; a first resistor operably connected to the input transistor, the first switch of the second set of switches, and the second and third switches of the first set of switches; a second resistor operably connected to the input transistor, the first switch of the first set of switches, and the second and third switches of the second set of switches; and, an output being operably connected to the input transistor and the third switch of both the first set and second set of switches, the output being operably responsive to the input transistor and the complementary set of switches wherein the mutually exclusive non-overlapping “on” states of the complementary set of switches alternately change the direction of current flow through the input transistor.