During EMC RE testing wireless charge detection , peak value, quasi-peak, average value of these three values respectively represent what meaning Wireless charge detection ? In the RE test process of EMC, these three values respectively represent the meaning of wireless charge detection : average detection: its characteristics are the same number of detector charge and discharge, especially suitable for continuous wave measurement. Peak detection: The number of charging intervals even narrow pulses can quickly charge stable values.
First: peak, quasi-peak, average worth meaning: the difference between the three is mainly concentrated with the difference in charge and discharge time of the detector average detection: the mostThe big feature is that the charge and discharge time constant of the detector is the same, which is especially suitable for the measurement of continuous wave.
This is the CE conduction test data in EMC. According to the regulatory requirements, both QP and AVG values must be within the limit value. Red represents the QP value, which is the quasi-peak value, and blue represents the AVG value, which is the average value.
A higher curve representing the peak detection, and a lower curve representing the mean detection. Electromagnetic Compatibility (EMC) is the magnitude of interference (EMI) and electromagnetic fields on electronic productsThe comprehensive evaluation of anti-interference ability (EMS) is one of the most important indicators of product quality, and the measurement of electromagnetic compatibility consists of test sites and test instruments. The expression
means that wireless charge detection We are 95% sure that the quasi-peak of the disturbance voltage of the injection supply is between 54 and 50 (dB m v).
According to EMC standards, the test receiver is required to have a peak, quasi-peak and average detector, and the general spectrum analyzer generally has a peak and average detector, without a quasi-peak detector.)/(3 2 5) = 5ω, R2= (3 2 5)/(3 2 5) =0.6Ω, R4= (2 x 5)/(3 2 5) =1Ω. Rob= (0.6 4) ∥ (1 1) =1 (Ω). Rab=Rao Rob=5, 1=5Ω. R is equal to 5, 5 is equal to 4Ω.
The basic problem of my teaching circuit analysis is shown in the figure. When t=0, the switch S is closed, and the circuit is in steady state before the switch is closed. Find Uc at t0. ... As shown in the figure, when t=0, the switch S is closed, and the circuit is in steady state before the switch is closed. oUc in t0 mode.
First analyze whether the circuit is in series or in parallel, the ammeter as a wire, the voltmeter as a break, can erase, simplify the circuit. Then according to the specific analysis of the question. The identification and judgment of the circuit include the judgment of the correct circuit and the wrong circuit, the judgment of the series circuit and the parallel circuit. Faulty circuits include missing necessary components in the circuit (necessary components are power supplies, electrical appliances, switches, wires), failure to form a current path, and open or short circuits.
1. Bigger is not better. There are great limitations in high-frequency circuits, and once the choice is not correct, it will affect the overall working state of the circuit. The larger the high-voltage capacitor, the stronger the current compensation ability provided by the IC, but the parasitic inductance will also increase, and some large-capacity high-voltage capacitors are larger, which will increase the cost, and are not good for air flow and heat dissipation.
2, therefore, the role of large capacitors and small capacitors in the circuit is different, the difference is the capacity size and use scenario, according to the specific circuit needs to choose the right capacitor can better play its advantages, improve circuit performance and reliability.
3, the capacity is different: small capacitance capacity is small enough to reach several P. Large capacitance capacity up to 10,000 μf. Different uses: large capacity capacitors can be used as power filter capacitors. Small capacity capacitors can be used as high-frequency resonant capacitors. Capacitors play an important role in tuning, bypass, coupling, filtering and other circuits.
4, thus reducing the high frequency performance of the capacitor, while the large capacitor often has a larger parasitic inductance, thereby reducing the filtering effect, affecting the stability of the circuit. Therefore, the capacitance capacity should be allocated according to demand in order to achieve the best performance of the appliance. The use of capacitors variesIt is good to have a large capacity, mainly to see where it is used, the large capacity is the large capacity, the small capacity is the small capacity, and the appropriate is important.
5, treble capacitor, different people have different hearing, the choice of treble capacitor is also different. The smaller the capacitor, the finer the high frequency, but the smaller the sound. Usually, the resonant frequency of the treble of the ordinary diaphragm is mostly around 1000-3000Hz. If the inner core is too small, the power is not enough, you can choose 3uF or 2uF. The inner core has 20 cores and can use 7uF.
6, high frequency signal ω, the need for small C; Low frequency signal ωSmall, you need big C. For a series circuit, it is best to have no response to the frequency, and the change in the incoming signal is immediately transmitted to the output end. Frequency response is a requirement for parallel capacitors. Charge and discharge the capacitor, large capacitor, very high frequency, very short time, how much electricity can not be released, the voltage at both ends of the capacitor is almost constant, and the large capacitor has poor response to high frequency signals.