← 返回 JSSC 论文列表JSSC 2007第11期RF & Wireless0.5μm BiCMOSLNA
A Digitally Controlled Variable-Gain Low-Noise Amplifier With Strong Immunity to Interferers
提出一种采用电容衰减器和电流分流技术的可变增益低噪声放大器，显著提高线性度和增益范围。
650 MHz时NF为1.5 dB，功耗15.4 mW，增益范围42.7 dB
可变增益放大器低噪声放大器电容衰减器电流分流DVB-H
▸创新点1：采用电容衰减器实现可变增益（方法创新）。通过精确控制电容衰减器的切换，实现了42.7 dB的宽增益范围，同时保持了低噪声系数（1.5 dB）和高线性度（IIP3达3.5 dBm），解决了传统可变增益放大器增益范围与线性度难以兼顾的问题。
▸创新点2：基于电流分流技术的数字增益控制（电路创新）。在共源共栅晶体管中引入电流分流技术，显著提升了中等增益设置下的线性度（IIP3从1.1 dBm提升至3.5 dBm），同时避免了传统增益控制方法导致的噪声性能恶化。
▸创新点3：针对DVB-H接收场景的优化设计（系统创新）。通过联合优化增益、噪声和线性度，使LNA在强干扰环境下仍能满足DVB-H接收的全部要求，实测结果与理论分析高度一致，验证了设计的鲁棒性。
▸创新点4：低功耗高性能的BiCMOS工艺实现（工艺创新）。在0.5μm BiCMOS工艺下实现15.4 mW的低功耗（2.9V供电），同时保持650 MHz时1.5 dB的优异噪声性能，展现了工艺与电路协同设计的优势。
Abstract
A variable-gain low-noise amplifier with capacitive step attenuators is presented. In order to improve linearity at medium gains settings, digital gain control is performed using a current-splitting technique at the cascode transistors. The fab- ricated LNA shows an IIP3 increase with constant OIP3, from 1.1 dBm at 25.8 dB gain to 3.5 dBm at 21.2 dB gain. Using capacitive attenuator control, a wide gain range of over 42.7 dB is achieved. Using a 0.5- m BiCMOS process, the proposed LNA shows an NF of 1.5 dB at 650 MHz and a power consumption of 15.4 mW under 2.9 V supply voltage. The fabricated tuner-IC, including the proposed LNA, satisfies all requirements pertinent to DVB-H reception, with sufficient margins for practical integra- tion. Under typical DVB-H reception scenarios involving strong interferers, measurement results and analytical calculations showed good consistency at various gain settings.