Capacitive voltage divider

In Fig. 6.1.8a the variable capacitors are configured as a capacitive voltage divider. Conceptually, the center electrode samples the electrostatic field set up by the sense... 

The input impedance of electrometers is of the order 10 2. Electrometers may be equipped with either capacitance or resistance voltage dividers to enable their voltmeter input range (typically 10 to 100 V) to be increased to 30 kV or more. The capacitance divider comprises an isolated target elec-... 

Another passive method is the transference function method (TFM) introduced by Muramatsu [6]. The method consists of an oscillator that drives a crystal through a known measuring impedance and a radiofrequency voltmeter which measures the transference modulus of the system. Muramatsu [6] neglected the effect of the parasitic capacitance and his expression for the quartz impedance resulted in a nonlinear relationship between the measured resistance R with the ac voltage divider and the value of R measured by an impedance analyser. Calvo and Etchenique [74] improved the method and introduced an analytical expression to fit the entire transfer function around resonance in order to obtain the same values of R, L and C as measured by a frequency response analyser. 

Other sensors, e.g. based upon the Hall effect, or capacitive or resistive voltage dividers, are not within the scope of - e and shall be manufactured in a different type of protection. 

However, this value is reduced by the capacitance of the discharge reactor itself, by that of any instrumentation voltage dividers, and by stray capacitances, so that the actual tuning capacitance used is somewhat lower and must be determined experimentally. 

A number of methods have been employed to increase the Unear output current limit of a detector. One method is simply to increase the bias current of the multiplier by using smaller resistor values in the voltage divider network connected to the dynodes. Special high-current multiplier models are in common use that have a total resistance across their dynodes of only 3 MS2, giving a bias current of > 600 ptA. These multipliers have Unear count rate limits of 20 X 10 cps (when operated at a gain of 10 ). Alternate approaches use a variety of specialized voltage divider networks to increase the linear limit of the detector. These networks incorporate zener diodes and additional capacitance to stabilize dynode voltages. ... 

The capacitor converts the charge pulse to a voltage pulse. The voltage is equal to the amount of charge divided by the capacitance of the capacitor, as given in Equation 6-8. 

The dielectric behavior is often studied by employing charging or polarization currents. Since polarization currents depend on the applied voltage and the dimensions of the condenser, it is customary to eliminate this dependence by dividing the charge, Q, by the voltage, V, to get a parameter called the capacitance (capacity), C ... 

The equivalent circuit of an electrochemical cell is shown in Fig. 5.6. It can be represented by a capacitive divider consisting of Cw and CAux connected in series. Figure out how the voltage V and charge Q are distributed across this divider when the resistances are (a) finite (b) infinite. 

If a layer of non-conductive medium is sandwiched between two electrodes and electricity passes through this assembly, electric charge will be stored at both electrodes. This assembly is called a capacitor. The capacitor is measured by its capacitance (C), which is represented by the stored electric charge, divided by the voltage drop across the two electrodes ... 

---