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各种CMOS数字功能都可用于很多模拟领域.例如,一个CMOS器件(MC74AC00)有可能成为一种小功率、低噪声宽带放大器和平衡混频器(参见附图).“与非”门1和2配置成一个自偏置推挽放大器.470K、1/4W电阻器可在一个标称偏置电位为+2.5V时与门输入(引脚1和5)保持平衡(Vcc/2).当引脚2和4连接在一起时,就可对放大器进行外部“使能”控制.当控制线处于“高态”(Vsc)时,放大器启动.偏置电阻器的两端在变压器T1和T2的中心点由0.01μF电容器进行交流旁路.变压器T1、T2和T3都是采用小型铁氧体环形磁芯的双绞线(传输线)型变压器.这些变压器的带宽和性能都是所选用的环形磁芯型线匝的数量和尺寸的函数.该电路的频响上限为60MHz.
For example, a CMOS device (MC74AC00) is likely to become a low-power, low-noise wideband amplifier and balanced mixer (see the figure). “NAND gates 1 and 2 is configured as a self-biased push-pull amplifier. The 470K, 1 / 4W resistor is balanced (Vcc / 2) with the gate inputs (pins 1 and 5) at a nominal bias potential of + 2.5V. The amplifier is externally ”enabled“ when pins 2 and 4 are connected together, and the amplifier is activated when the control line is at ”high" (Vsc). Both ends of the bias resistor are connected between transformers T1 and T2 AC bypass by a 0.01μF capacitor Transformer T1, T2 and T3 are twisted-pair (transmission line) transformers with a small ferrite toroidal core The bandwidth and performance of these transformers are selected rings As a function of the number and size of core turns. The upper limit of the frequency response of this circuit is 60MHz.