| 摘要 |
A circuit configuration for actuating a power amplifier transistor is described, which is intended to ensure that the power consumption is as low as possible while having a variable output power. Such a circuit is particularly suitable for amplifiers in mobile telephones. In particular, a circuit configuration is described which controls at least two different operating points for at least two different output power ranges. At a first operating point, the quiescent current in the power amplifier transistor is controlled by a first balanced circuit having a temperature-compensating active feedback circuit. At a second operating point, the quiescent current in the power amplifier transistor is controlled by a second balanced circuit, having a second feedback circuit. A third operating range is used in saturation mode, which ensures maximum power efficiency with the maximum output power, although this results in the gain being only partially linear.
|
