发明名称 |
DIFFERENTIAL AMPLIFIER DESIGN AS THE PREAMP OF DMM |
摘要 |
An amplifying circuit comprises a differential input stage having a first input terminal, a second input terminal, and an intermediate node, wherein the differential input stage is configured to generate a differential current flowing through the intermediate node in response to an input voltage difference between the first and second input terminals. The amplifying circuit further comprises a first current source coupled to the intermediate node, which is configured to provide a first bias current which allows the differential current to vary within a predetermined range. The amplifying circuit further comprises an output terminal coupled to the intermediate node, and a second current source coupled to the intermediate node and configured to provide a second bias current. The second bias current compensates the differential current and the first bias current and produces an output current flowing through the output terminal in a predetermined direction. A measurement device is also described. |
申请公布号 |
US2015130483(A1) |
申请公布日期 |
2015.05.14 |
申请号 |
US201414539599 |
申请日期 |
2014.11.12 |
申请人 |
Danaher (Shanghai) Industrial Instrumentation Technologies R&D Co., Ltd. |
发明人 |
Yao Hong;Yang Yong;Qui Hua |
分类号 |
H03F3/45;G01R19/00 |
主分类号 |
H03F3/45 |
代理机构 |
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代理人 |
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主权项 |
1. An amplifying circuit, comprising:
a differential input stage having a first input terminal, a second input terminal, and an intermediate node, wherein the differential input stage is configured to generate a differential current flowing through the intermediate node in response to an input voltage difference between the first and second input terminals; a first current source coupled to the intermediate node and configured to provide a first bias current which allows the differential current to vary within a predetermined range; an output terminal coupled to the intermediate node; and a second current source coupled to the intermediate node and configured to provide a second bias current which compensates the differential current and the first bias current and produces an output current flowing through the output terminal in a predetermined direction. |
地址 |
Shanghai CN |