The measured gain is +13 dB when phase is -180°, so the gain margin is minus 13 dB. At a gain of 0 dB, the measured phase is minus 215°, so the phase margin is minus 35° at the gain crossover point. This system is unstable. Bode plot vs. load transient tes...
增益余量(gain margin)是指:相位为0时所对应的增益大小,以分贝(dB)为单位来表示(图2)。 穿越频率(crossover frequency)是指:增益曲线穿越0dB时的频率点(图2)。 相位余量的作用是确保在一定条件下(包括元器件的误差、输入电压变化、负载变化、温升等)系统都能够稳定,使用在标称输入额定负载室温下,要有45度的余量。
穿越频率(crossover frequency),带宽(bandwidth)ωb还有自然频率(natural frequency)ωn是可以近似相等的。因此穿越频率的大小也会影响响应的速度。 2.开环Bode Plot曲线的形状 我们在之前提到过开环Bode Plot的低频与系统稳态误差对应相关,高频部分与噪音抑制对应相关。联系本篇中的Bode Gain-Phase关系,我们又对穿越频...
This video explains how a Bode plot describes the frequency response of a linear time-invariant system and the plot’s primary characteristics, such as the DC gain, roll-off rate, natural frequency, crossover frequency, and bandwidth frequency. You will also learn how to create a Bode plot ...
Bode plot measured. Looking at the measuerement Bode plot, DC gain was 1kHz of 24dB. Cross over frequency was 2MHz, phase margine was 39 degree. Looking at the Datasheet Fig52, DC gain was 1kHz of 55dB. Cross over frequency was 300kHz, Phase margine was...
Gain Crossover Frequency:It refers to the frequency at which the magnitude curve cuts the zero dB axis in the bode plot. Phase Crossover Frequency: It refers to the frequency at which the phase curve cuts the negative times the 180o axis in this plot. ...
By adjusting Rp and Cff, crossover frequency is set at one-sixth the switching frequency with a phase margin of 66 degrees. I conducted these experiments with the reference design, Step-down converter for powering rails in Altera Arria V FPGA (PMP8824). Figure 4. Bode plots measured with ...
The crossover frequency of the 12mV ramp is around 29kHz, with a 95-degree phase margin. The crossover frequency of the 6mV ramp is about 102kHz, with a 117-degree phase margin. Figure 4. Bode Plot Comparison with Different Ramp Values on the TPS548B22 EVM As you can see from ...
The .step command sets the frequency resolution and range over which to perform the analysis. In this example, the simulation runs from 1 kHz to 1 MHz using a resolution of three points per octave. Bode plot measurements are accurate up to fSW/2, so the upper frequency limit should...
Gain crossover frequency (ωgc): It is the frequency at which the magnitude of G(s) H(s) is unity. |G(jω)H(jω)|ω=ωgc=1 In the Nyquist plot, the gain at phase cross-over frequency is the gain at which the plot cuts the negative real axis. Calculation: The given trans...