Filtering device with low-pass filtering function and band-pass filtering function

摘要

A filtering device, applicable in a transceiver, includes: a capacitive circuit coupled to an amplifying circuit by a first capacitive configuration or by a second capacitive configuration; and a resistive circuit coupled to the amplifying circuit by a first resistive configuration or by a second resistive configuration; wherein when the capacitive circuit is the first capacitive configuration, the filtering device is used to perform a first filtering process upon a receiving signal of the filtering device, and when the capacitive circuit is the second capacitive configuration, the filtering device is used to perform a second filtering process upon a transmitting signal of the filtering device.

主权项

1. A filtering device, applicable in a transceiver that processes a receiving signal and a transmitting signal, comprising:
a capacitive circuit, configured to form a first capacitive configuration or a second capacitive configuration by selectively coupling a plurality of capacitors to an amplifying circuit, wherein the capacitors coupled to the amplifying circuit in the first capacitive configuration and the second capacitive configuration are not exactly the same; and a resistive circuit, configured to form a first resistive configuration or a second resistive configuration by selectively coupling a plurality of resistor to the amplifying circuit, wherein the resistors coupled to the amplifying circuit in the first resistive configuration and the second resistive configuration are not exactly the same; wherein the filtering device is operative to filter the receiving signal when the capacitive circuit operates in the first capacitive configuration and to filter the transmitting signal when the capacitive circuit operates in the second capacitive configuration, and the filtering device functions as a band-pass filter in the first capacitive configuration and a low-pass filter in the second capacitive configuration.