I have been tasked to design a clamp circuit to clamp the negative extreme of a periodic input waveform to −5 V. I can use diodes, zener diodes, and resistors of any values required. I will assume a 0.6 V forward drop for all diodes and that the Zener diodes have an ideal characteristic in the breakdown region.
Powersupply voltages of ±15 V are available.
For Input Voltage having maximum amplitude greater than 5 Volts, I just have to do positive clamping. For example, with Vin = 6sin(100pit), the entire waveform will move up by 1V. Hence my DC or Q point will be 1V.
However, I am struggling with two things.
- If Input AC Voltage is less than 5V, for example, assuming Vin = 4V, in that case, the negative peak will be at -4V, meaning that in order to clamp this to -5V, I have to go down by 1V. How do I achieve this here?
- What is the use of that 15V DC source here? How does this affect the circuit allowing me to achieve my goal?
I have attached the solution that I have from my Professor, but I could not grasp his explanation unfortunately.
Any help will be appreciated.
