US 12,388,420 B2
Noise filter circuit with controllable transistor off-resistance and associated noise filtering method
Chuan-Hung Hsiao, Hsinchu (TW); and Sung-Han Wen, Hsinchu (TW)
Assigned to MEDIATEK INC., Hsinchu (TW)
Filed by MEDIATEK INC., Hsin-Chu (TW)
Filed on May 8, 2023, as Appl. No. 18/144,839.
Claims priority of provisional application 63/347,601, filed on Jun. 1, 2022.
Prior Publication US 2023/0396152 A1, Dec. 7, 2023
Int. Cl. H03M 1/66 (2006.01); H03H 11/04 (2006.01)
CPC H03H 11/04 (2013.01) 20 Claims
OG exemplary drawing
 
1. A noise filter circuit comprising:
a filter, comprising:
a first transistor, arranged to have off-resistance when turned off or operated under sub-threshold region, wherein the first transistor comprises:
a control terminal, arranged to receive a first control voltage, wherein the control terminal is not directly tied to a reference voltage;
a first connection terminal; and
a second connection terminal; and
a charge storage component, having one terminal coupled to the second connection terminal of the first transistor; and
a transistor off-resistance control circuit, coupled to the first transistor and arranged to set the first control voltage for controlling the off-resistance of the first transistor.