Clipper Circuits (2131006) PDF

# Electronic Devices and Circuits (2131006) ## Clipper Circuits **LET'S REMOVE UNWANTED PART OF SIGNALS** ## Index 1. What are clipper circuits? 2. Types of clipper Circuits. 3. Unbiased positive clipper. 4. Unbiased negative clipper. 5. Biased series positive clipper. 6. Biased series negative...

# Electronic Devices and Circuits (2131006) ## Clipper Circuits **LET'S REMOVE UNWANTED PART OF SIGNALS** ## Index 1. What are clipper circuits? 2. Types of clipper Circuits. 3. Unbiased positive clipper. 4. Unbiased negative clipper. 5. Biased series positive clipper. 6. Biased series negative clipper. ## What are clipper circuits? * Clipper Circuits remove the portion of a signal that is above or below a certain reference level. * An example of a clipper is a half-wave rectifier. This circuit removes the part of the signal below zero, only allowing the positive (or negative) parts to pass through. * Clipping Circuits are also known as limiters, amplitude selectors, or slicers. ## Types of Clipper Circuits **Clipper Circuits:** - Unbiased Clipper Circuit - Biased Clipper Circuit **Unbiased Clipper Circuit:** - Unbiased Positive Clipper - Unbiased Negative Clipper **Biased Clipper Circuit:** - Biased Positive Clipper - Biased Negative Clipper ## Note: - All explanations assume the diode is ideal. ## Unbiased Positive Clippers * Positive Clippers are used to clip positive portions of the input signal and allow the negative portions to pass through * The figure below shows the input and output signal along with a circuit. The positive cycle is completely clipped off by the clipper. ## Continued... * The diagram shows the same clipper configuration, but the diode is replaced with its equivalent circuit model. * When the input signal goes positive, the cathode terminal of the diode attains a higher potential than the anode. * This makes the diode reverse biased. The diode becomes an open switch. * As the diode acts as an open switch, no current flows through the load, and no output appears across the load. This is why the positive cycle is completely clipped off. ## Unbiased Negative clippers * Negative clippers are used to clip negative portions of the input signal and allow the positive portions to pass through. * The figure shows the input and output signal along with the negative clipper. The negative cycle is clipped off. ## Continued... * The diagram shows the same clipper configuration, but the diode is replaced with its equivalent circuit model. * When the input signal goes positive, the anode terminal of the diode attains a higher potential than the cathode. This makes the diode forward biased. * The diode can be modeled as a closed switch. No current flows through the load, and no output appears across the load. This is why the negative cycle is clipped off. ## Biased series positive clipper * The clipping of the signal takes place as soon as the input signal goes positive. * To change or adjust the clipping level of the AC voltage, an external biasing voltage must be used. This figure shows a biased (series) clipper. ## Working * **Diode acts as an open switch:** Output voltage is zero for signals greater than $V_b$. * **Diode acts as a closed switch:** Output follows the input. Minimum value of the output is $V_b$. ## Biased Series negative Clipper * The clipping of the signal takes place as soon as the input signal goes negative. * To change or adjust the clipping level of the AC voltage, an external biasing voltage must be used. This figure shows a biased (series) clipper. ## Working * **Diode acts as an open switch:** Output voltage is zero. * **Diode acts as a closed switch:** Output follows the input. Maximum value of the output is $V_b$. ## Thank You