Circuit rise time

It is frequently important to determine electrode resistance to account for any contributions to iR drop and circuit rise time due to the electrode itself. Two general strategies are available for this purpose. One strategy for accurately determining p is to use a four-point probe (see Fig. 11.2) for the measurement [6]. This device supplies a controlled current to be passed through the film via... 

For adequate protection of the machine it is essential to know the amplitude, F, and the rise time, /, of the severest voltage surge (FOW) that may occur on the system. It is recommended that the actual field tests be conducted for large installations according to the recommended simulation test circuits, noted above, to ascertain these surges. 

Corona discharges have been investigated extensively for NO removal [38-54], The effect of electrodes configuration, electrical circuit, gas composition and flow rate were studied. When the discharge was operated in pulsed mode, the influence of pulse rise time, duration, and repetition frequency, as well as the effect of the voltage polarity on NO conversion, were considered by numerous authors. 

The Performance Analysis capabilities of Probe are used to view properties of waveforms that are not easily described. Examples are amplifier bandwidth, rise time, and overshoot. To calculate the bandwidth of a circuit, you must find the maximum gain, and then find the frequency where the gain is down by 3 dB. To calculate rise time, you must find the 10% and 90% points, and then find the time difference between the points. The Performance Analysis gives us the capability to plot these properties versus a parameter or device tolerances. Hie Performance Analysis is used in conjunction with the Parametric Sweep to see how the properties vary versus a parameter. The Performance Analysis is used in conjunction with the Monte Carlo analysis to see how the properties vary with device tolerances. In this section we will plot the bandwidth of an amplifier versus the value of the feedback resistor. See Sections 9.B.3 and 9.E to see how to use the Performance Analysis in conjunction with the Monte Carlo analysis. 

We see that the slowest rise time occurred for a value of R VSl equal to 10 kQ. This example will be continued in Section 6.L. You may wish to save this circuit before running the circuit of EXEHCISE B-10. 

We can now see small marks on the trace that indicate the locations of the data points. This plot shows us that the rise time of the circuit is a linear function of the collector resistor value. 

In order to correlate the breadboard to the SPICE circuit, a 5 V pulse replacements was applied with a rise time of 100 ns by using the following command in a V source ... 

For digital circuits, the electrical length of the line can be defined relative to the signal rise time. A common rule of thumb for simple lines with no branches is that interconnections must be treated as transmission lines when the round-trip transit time of the signal, 2t pdZ, exceeds the signal rise time, tr (37). This rule defines a critical line length (Zc) given by... 

It can be shown from Figure 11 and Equation 1 that the rise time of the signal will be controlled by the RC time constant of the circuit loading the pyroelectric current generator. The simplest case is where the heat flow into the pyroelectric is one dimensional as shown in Figure 12. Then the signal across the parallel load resistor of the pyroelect-ic element is... 

The rise time of the detector equivalent circuit, in most cases a negligible quantity,... 

At high V the relative positions of the three electrodes need to be optimized and the size of the working electrode needs to be reduced in order to minimize resistance and capacitance problems [143]. The quality of the potentiostat, usually reflected by the rise time, also becomes critical at high v. The two factors are actually not separable since the electrochemical cell is inherently a part of the total electronic circuit. 

Both Trissl [58] and Rayfield [59] have constructed ultrafast biological photodiodes and Rayfield has demonstrated a rise time of the photoelectric of the order of a few picoseconds. That an oriented BR thin film constitutes a photocell is apparent from our equivalent-circuit analysis. However, the claim... 

In a microprocessor-based ventilator, an electronically actuated valve can be employed that has adequate dynamic response ( 20 ms rise time) to regulate PEEP. For this purpose, the pressure in the patient s breath delivery circuit is measured using a pressure transducer (Figure 18.8). The microprocessor initially opens the exhalation valve completely to minimize resistance to expiratory flow. At the same time, it samples the pressure transducer s output and begins to close the exhalation valve as the pressure begins to approach the desired PEEP level, Because the patient s exhaled flow is the only source of pressure, if the airway pressure drops below PEEP, it cannot be brought back up until the next inspiratory period. Hence, an overrun (i.e., a drop to a level below PEEP) in the closed-loop control of PEEP should be avoided. 

The principal elements in commercial TDS equipment are a tunnel diode generator of repetitive voltage pulses with rise time of ca. 30 ps at a rate of ca. 100 KHz, probe circuits for observation of these pulses and their reflections in a coaxial line, and sampling oscillo-... 

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