V i O) the output waveform of the Circuit is the same as that of series negative clipper. V i < O) and as an open switch for a positive input voltage (i.e. In such a circuit the diode acts as a closed switch for a negative input voltage (i.e.
Figure 7: Shunt Parallel Negative Clipper The negative clipper has allowed to pass the positive half cycle of the input voltage and clipped the negative half cycle completely Fig 7 shows the shunt (parallel) negative clipper. it will be interesting to know that if the polarity of the bias voltage is reversed, the resulting circuits will be as shown in Fig 6(b) Here the input signal lying above the voltage -V B is clipped the waveforms of the of the output voltage are also shown with figures Figure 6: Bias Shunt Parallel Positive Clipper SHUNT OR PARALLEL NEGATIVE CLIPPER V i > 0 and as an open switch when the input voltage is negative (i.e. The diode acts as a closed switch when the input voltage is positive (i.e. The output is in parallel with the diode hence the circuit name parallel clipper the parallel clipper can limit either the positive or negative alternation of the input signal Fig 5 shows the circuit of a shunt positive clipper In this circuit. In this circuit clipping take place during the negative half cycle only when the input voltage V i > V B she clipping level can be shifted up or down by varying the bias voltage ( -V B) Figure 4: Series Negative Clipper with Bias SHUNT OR PARALLEL POSITIVE CLIPPERĪ parallel clipper circuit uses the same diode theory and circuit operation a resistor and diode are connected in series with the input signal and the output signal is developed across the diode. It may be observed that if it is desired to remove or clip the negative half -cycle of the input, the only thing is to be done is to reverse the polarities of the diode in the circuit shown in Fig 1 such a clipper is then called a series negative clipper SERIES-NEGATIVE CLIPPER WITH BIASįig 4 shows the circuit of a biased series negative diver. Therefore the diode is reverse biased and it acts as an open switch, Thus there is no voltage drop across the resistor during the negative half cycle as shown in the output waveform. During the negative half cycle of the input voltage, the terminal B is positive with respect to the terminal A. Figure 3: Series Negative Clipperĭuring the positive half cycle pf the voltage, the terminal A is positive with respect to the terminal B There for the diode is forward biased and it acts it as a closed switch As a result ,all the input voltage appears across the resistor as shown in Fig 3(b). In a series negative clipper a diode is connected in a direction appositive to that of a positive clipper Fig 3 shows the circuit of a negative clipper. The chipping level can be shifted up or down by varying the bias voltage (V B) It may be observed that the clipping takes place during the positive cycle only when the input voltage is greater thence battery voltage (i.e. Figure 2: Series Positive Clipper with Bias For this purpose a biased clipper is used Fig 2 shows the circuit of a biased series positive clipper.
Sometimes it is desired to remove a Small portion of positive or apposite halt cycle of the signal voltage (input signal).
Due to this reason the circuit is called series positive clipper. Hence the circuit of the Fig 2.1 is called a positive Clipper Here it may he noted the diode acts a series switch between the source and load. However a positive Clipper is that which removes or clips the positive half completely. All the input voltage is dropped across the resistor as shown in the output wave form.Ĭlippers prevent either or both polarities of a wave form exceeding a specific amplitude level. Thus there is on voltage drop across diode during the negative half cycle of the input voltage. Therefore it forward biases the diode and it acts as a closed switch. Figure 1: Series Positive Clipperĭuring the negative half cycle of the input voltage the terminal B is positive with respect to A. This reverse biases the diode and it acts as an open switch Therefore all the applied voltage drops across the diode and none across the resistor As a result of this there is no output voltage during the positive half cycle of the input voltage. During the positive half of the input voltage, the terminal A is positive with respect to B. In a series positive clipper, a diode is connected in series with the output, as shown in Fig 1(a).
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