US 12,143,071 B2
Trimming circuit of differential amplifier
Jun Zhang, Shanghai (CN); and Zhian Zhang, Shanghai (CN)
Assigned to Shanghai Analogy Semiconductor Technology Ltd., Shanghai (CN)
Appl. No. 17/437,694
Filed by SHANGHAI ANALOGY SEMICONDUCTOR TECHNOLOGY LTD., Shanghai (CN)
PCT Filed Jul. 12, 2019, PCT No. PCT/CN2019/095863
§ 371(c)(1), (2) Date Sep. 9, 2021,
PCT Pub. No. WO2020/258369, PCT Pub. Date Dec. 30, 2020.
Claims priority of application No. 201910573193.2 (CN), filed on Jun. 28, 2019.
Prior Publication US 2022/0166390 A1, May 26, 2022
Int. Cl. H03F 3/45 (2006.01); H03F 1/56 (2006.01)
CPC H03F 1/56 (2013.01) [H03F 3/45475 (2013.01); H03F 2203/45624 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A trimming circuit of differential amplifier, wherein,
an output terminal of the differential amplifier is coupled to a first input terminal of the differential amplifier through a first voltage-dividing resistor;
a shift voltage is coupled to a second input terminal of the differential amplifier through a second voltage-dividing resistor;
the first voltage-dividing resistor and the second voltage-dividing resistor are respectively formed to be a T-shaped resistor network structure;
the T-shaped resistor network structure comprises:
a k-bit resistive network coupled to a T-shaped node and a reference power supply terminal, wherein a low n-bits of the k-bit resistive network is a R-2R resistive network, and part of branches of the low n-bits are connected in series with at least one trimming resistor, and each trimming resistor is connected in parallel with a switch, wherein k and n are positive integers greater than or equal to 1, and k≥n.