(Solved): c) Calculate the current I in the following circuit. Please use ideal diode approximation w ...

c) Calculate the current I in the following circuit. Please use ideal diode approximation with $${\mathrm{V}}_{\mathrm{ON}}=0.7\mathrm{V}$$. Show your workings. [5 marks] d) The Light Emitting Diodes in the following circuit need a voltage of $$1.5\mathrm{V}$$ and a current of $$100\mathrm{mA}$$ each to operate optimally. Design the value of $$R$$ to achieve this condition. Show your workings. [5 marks] After the amplification, the high frequency noise added to the useful signal needs to be rejected. Design an appropriate filter based on a single ideal op-amp with a voltage attenuation of $$20\mathrm{dB}$$ at the frequency of $$10X.Y\mathrm{kHz}$$, where $$X$$ and $$Y$$ are the last two digits of your student number. For example, if your student number is 1234567 , the cut-off frequency is $$106.7\mathrm{kHz}$$.