clippers and clampers - cie-wc.educie-wc.edu/diode-clipper-and-clampers-lecture-8-18-11.pdf ·...
TRANSCRIPT
![Page 2: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/2.jpg)
First clipper circuit
• Diode is forward biased during positive half cycle
– This makes the positive potential 0.7V
![Page 3: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/3.jpg)
• Output swings from 0.7V positive to -50V negative
![Page 4: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/4.jpg)
Second clipper circuit
• Diode is forward biased during negative half cycle
– This makes the negative potential 0.7V
![Page 5: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/5.jpg)
• Output swings from +24V positive to -0.7V negative
![Page 6: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/6.jpg)
Third clipper circuit
• Since diodes are in series, each branch will drop 0.7V + 0.7V = 1.4V
– Branches are in parallel
![Page 7: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/7.jpg)
• Output swings from +1.4V positive to -1.4V negative
![Page 8: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/8.jpg)
Fourth clipper circuit
• First, determine potential at VBIAS
– VBIAS = 1k
6.8k+1k15 =
0.128 15 = 1.92V
• Since diode requires positive potential of 0.7V and adds to VBIAS, maximum positive potential becomes 2.62V
![Page 9: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/9.jpg)
• Waveform swings from +2.62V positive to -20V negative
![Page 10: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/10.jpg)
First clamper circuit
• DC potential is pk – 0.7V = 14.3V
– This becomes the zero reference line for the AC, so it will go 15V above and 15V below this line
![Page 11: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/11.jpg)
• Output swings from +29.3V positive to -0.7V negative
![Page 12: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/12.jpg)
Second clamper circuit
• DC potential is pk – 0.7V = 29.3V
– This becomes the zero reference line for the AC, so it will go 30V above and 30V below this line
![Page 13: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/13.jpg)
• Output swings from +0.7V positive to -59.3V negative
![Page 14: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/14.jpg)
Third clamper circuit
• This one charges the capacitor during the positive alternation, and this will then discharge during the negative alternation.
• This makes the output at maximum a straight line of 40V (2Vpk)
![Page 15: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/15.jpg)
• However, since the diode is not perfect we need to use the first approximation (simplified diode)
– This means we need to subtract 0.7V for the one diode that charges the capacitor (39.3V)
– And lest we forget, subtract the potential for the second diode as well (38.6V)
![Page 16: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/16.jpg)
• Output is pulsating wave (ripple) that rises to a maximum potential of 39.3V and descends to a minimum potential of 38.6V
![Page 17: Clippers and Clampers - cie-wc.educie-wc.edu/Diode-Clipper-and-Clampers-lecture-8-18-11.pdf · during positive half cycle –This makes the positive potential 0.7V •Output swings](https://reader031.vdocuments.us/reader031/viewer/2022021718/5b7a13fc7f8b9ad77e8ed443/html5/thumbnails/17.jpg)