Patent ID: 8253447
Filing Date: 2012-08-28
Classification: H03D

Abstract:
1. An apparatus for frequency conversion, comprising: an analog-to-digital (A/D) converter, receiving and sampling an input signal according to a sampling frequency for producing a first digital signal, and the sampling frequency and the frequency of the input signal having a correspondence; a sign conversion circuit, used for receiving the first digital signal, and performing a sign conversion on the first digital signal, thereby sign-converting the first digital signal into a second digital signal; a first switching module, used for selecting one of the first digital signal and the second digital signal as an output signal according to the sampling frequency; a filter, coupled to the first switching module, used for filtering the output signal from the first switching module, and producing a filter signal; and a second switching module, coupled to the filter, used for outputting the filter signal to a first output path or a second output path alternately according to the sampling frequency.