放大器
利用这些示例了解如何对不同类型的放大器进行建模。
精选示例
Audio Power Amplifier with H-Bridge
An H-bridge configuration switching audio power amplifier circuit. Switching audio power amplifiers are more efficient than conventional power amplifiers as switching devices are operating only in the fully-on and fully-off states. This audio power amplifier uses a 1MHz switching frequency and has a PI feedback controller to ensure that output voltage tracks the 2kHz and 2.5kHz sine wave inputs. The power spectrum is plotted in the Spectrum Analyzer, and can be used to inform selection of controller and filter parameters.
E 类射频放大器
此模型展示了一款 E 类射频放大器，其电路参数针对 80 米波长选定。E 类放大器可实现高效率，因为 MOSFET 永远不会同时出现高 Vds 和高 Ids。负载网络用于调整电压和电流波形。此模型可用于验证电路是否正常运行，并帮助选择组件。电路的正常运行对源极电阻 R_source 尤为敏感。两个 MOSFET 的电容参数采用 FQA11N90 器件的典型参数。
Differential Pair Amplifier
A differential pair amplifier circuit. The circuit can be used to explore the properties of a differential pair amplifier. The model can be tested using differential and common-mode inputs. The balanced output has zero gain in common-mode provided that the two transistors have identical properties.
Low-Noise Amplifier
A typical low-noise audio amplifier circuit. Resistor R2 provides negative feedback to stabilize the overall amplifier gain, making it independent of transistor open-loop forward transfer gain. Circuit gain is approximately defined by (R1+R2)/R1 = 101. The simulation shows that it takes the circuit a few seconds to settle to its steady operating point, and that the output is initially clipped. Input u and output y are included to support linearization.
含噪运算放大器建模
此示例展示了如何在电气仿真中加入噪声。该电路对了一个高频滚降频率为 10 MHz 的放大器进行了建模。Band-Limited Op-Amp 模块用于添加噪声。Voltage Source 模块 Vn 指定等效电压噪声密度为 20 nV/Hz^0.5。您还可以通过将两个 Resistor 模块的噪声模式参数设置为 Enabled 来添加来自电阻器 R1 和 R2 的热噪声。但是，通过使用不同的噪声源组合运行此模型，可以看到主要的噪声源是等效噪声电压。
Strain Gauge and Wheatstone Bridge
How to model a strain gauge and measurement amplifier. The strain gauge forms one leg of a Wheatstone bridge, which is connected to a differential amplifier. A second op-amp is then used to both amplify and apply a low-pass filter to the measurement signal. The op-amps are modeled at a system level, with the user specifying parameters such as open-loop bandwidth, gain and maximum slew rate. In this circuit, the dynamics are primarily set by the low-pass filter. The op-amp bandwidth and maximum slew rate have little impact on the step response.
RF Power Amplifier Characterization Test Harness
Defines a test harness to estimate a non-linear behavioral model of a RF power amplifier from a Simscape™ Electrical™ simulation model.
RF Transistor IV Characteristics Test Harness
Defines a test harness to estimate the I-V characteristics of a bipolar transistor from a Simscape™ Electrical™ simulation model.
开关音频功率放大器
此示例展示了一个开关音频功率放大器电路。开关音频功率放大器比传统功率放大器更高效，因为开关器件仅在完全导通和完全关断状态下工作。此音频功率放大器采用 1 MHz 的开关频率，并配备 PI 反馈控制器，可确保输出电压能够跟踪 2 kHz 和 2.5 kHz 的正弦波输入。频谱分析仪中绘制了功率谱，可为控制器和滤波器参数的选取提供依据。
