A VSWR-protected silicon bipolar RF power amplifier with soft-slope power control
A VSWR-protected silicon bipolar RF power amplifier with soft-slope power control
复制标题
具有软斜率功率控制的 VSWR 保护硅双极射频功率放大器
DOI：
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发表时间：
2005
影响因子：
5.4
通讯作者：
G. Palmisano
中科院分区：
文献类型：
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作者：
A. Scuderi;L. Paglia;A. Scuderi;F. Carrara;G. Palmisano
本文介绍了一种具有负载失配保护和软坡功率控制功能的1.8 ghz功率放大器的设计和性能测试。负载不匹配引起的击穿可以通过在过电压条件下将射频功率衰减到最后一级来避免。这是通过反馈控制系统完成的，该系统检测输出集电极节点的峰值电压，并通过改变电路增益将其值箝制到给定的阈值。输出功率控制的问题也得到了解决。为此，提出了一种温度补偿偏置网络，根据指数定律改变电路的静态电流，可以实现适度的功率控制斜率（dB/V）。该非线性功率放大器采用低成本硅双极工艺，击穿电压为6.4 v。它提供33.5 dbm饱和输出功率，最大功率增加效率为46%，在标称3.5 v电源电压下增益为36db。该器件能够承受高达5.1 v电源电压的10:1负载驻波比。在-15 dBm和饱和输出功率水平之间，功率控制斜率小于80 dB/V。
This paper presents the design and measured performance of a 1.8-GHz power amplifier featuring load mismatch protection and soft-slope power control. Load-mismatch-induced breakdown can be avoided by attenuating the RF power to the final stage during overvoltage conditions. This was accomplished by means of a feedback control system, which detects the peak voltage at the output collector node and clamps its value to a given threshold by varying the circuit gain. The issue of output power control has been addressed as well. To this end, a temperature-compensated bias network is proposed, which allows a moderate power control slope (dB/V) to be achieved by varying the circuit quiescent current according to an exponential law. The nonlinear power amplifier was fabricated using a low-cost silicon bipolar process with a 6.4-V breakdown voltage. It delivers a 33.5-dBm saturated output power with 46% maximum power-added efficiency and 36-dB gain at a nominal 3.5-V supply voltage. The device is able to tolerate a 10:1 load standing-wave ratio up to a 5.1-V supply voltage. Power control slope is lower than 80 dB/V between -15 dBm and the saturated output power level.