| 摘要 |
The invention relates to a mixer circuit comprising an input node for receiving an input signal, a first output node 202 , and a second output node 203 , voltage to current conversion means and switching means operatively coupled to each other and to the input node, the first output node and the second output node to generate a mixed input signal at the first output node and the second output node in response to an oscillator signal. In an embodiment the voltage to current conversion means comprises a first and a second voltage to current converter, implemented as N-MOSFETs M 2 and M 3, with their gates connected to the input node. The drain of M 2 is connected to the first output node 202, while the drain of the M 3 is connected to the second output node M 3. The source of M 2 is connected to the switching node 221, while the source of M 3 is connected to the second switching node 222. The switches SW are arranged to couple the first switching node 221 to a first supply voltage VDD and the second switching node 222 to a second supply voltage VSS during a first phase of the oscillator signal, and the first switching node 221 to VDD and the second switching node 222 to VSS during a second phase of the oscillator signal. The mixer circuit according to the invention may operate at low supply voltages by using switches connected only to the supply voltages VSS and VDD. Mixing is achieved by voltage to current converters GM 1 and GM 2, which are alternatingly activated by the switches SW.
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