| 摘要 |
PROBLEM TO BE SOLVED: To improve linearity and suppress power consumption.SOLUTION: An amplifier includes: front stage FETs 22-26b; back stage FETs 28a-28d connected in series with the front stage FETs; first matching circuits 30-36b connected to the front stage FETs; and second matching circuits 36a-38b connected to the back stage FETs. A band characteristic matched by the second matching circuits is narrower than a band characteristic matched by the first matching circuits. A gate bias voltage of the back stage FETs is applied in such a value as causes a drain idle current per unit gate width of the back stage FETs to be lower than a drain idle current per unit gate width of the front stage FETs. |
