| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a variable gain amplifier capable of acquiring a voltage gain at a previous stage with a small current even when operated at a high frequency.SOLUTION: The variable gain amplifier includes: a transconductance amplifier array 10 formed by connecting, in parallel, unit transconductance amplifiers 11-1 to 11-N for leading-in an electric current proportional to an input voltage Vfrom a power supply terminal 1; a control section 13 for controlling on and off operations of the unit transconductance amplifiers 11-1 to 11-N; and current shunts 14-1 to 14-(N-1) for splitting an electric current led in from the power supply terminal 1 into the unit transconductance amplifiers 11-2 to 11-N and output terminals 6, 7.</p> |
