Sir please make videos on SRAM, DRAM and boot strapping. 🙏
@lokendrasinghlodhi718
11 ай бұрын
Dear Sir Can you please make a vidio on this type of Question (asked in Texas Instrument) : An amplifier has a non-linear response given by Vo = Vin + Vin^3 at all frequencies. When a sine wave of amplitude 1V is input to the amplifier, the output of the amplifier contains a harmonic at -80 dBm. The amplifier output goes to a low pass filter with a 3 dB bandwidth of 1 MHz. What s the approximate amplitude of the harmonic at the output of the low pass filer if the input to the amplifier is a 3.33 MHz sine 'wave with an amplitude that is equal to 0.5 Volts? Or Atleast please give hint!
@chembiyant456
11 ай бұрын
Hi Lokendra, Non linear amplifiers characterised by vout=k1*vin+k2*vin^2+k3*vin^3+...kn*vin^n+....., produces harmonics of the input frequency. The problem you have here is a memoryless non-linearity (which means the non-linearity equations (or nonlinear characteristics) is the same irrespective of the input frequency of the signal). If the input amplitude is decreased by a factor, say x, then the power of the first harmonic will decrease by the same factor (this follows from linearity) x or 20 log(x). The n^th harmonic component decreases by a factor 20log(x^n)=n20log(x) as you can see from the non-linear characteristics that the nth harmonic term depends on vin^n. In this example the input signal amplitude is decreased by a factor 1/2 (it goes from 1 V to 0.5 V), so the first harmonics decreases by 6 dB (or -6 dB in absolute terms) and the third harmonic level decreases by 20log(1/2^3)=18 dB. So in this example the third harmonic power decreases to -80 dBm-18=-98 dBm. Now this output is then passed through a first order unity gain low pass filter (Im assuming first order unity gain as the order and dc gain are not mentioned here) of 1 MHz bandwidth. The third harmonic frequency for an input of frequency 3.333 MHz is 3*3.333 MHz=10 MHz. Since it is a first order low pass filter, it attenuates the signals after the bandwidth at the rate of -20 dB/decade, 10 MHz is a decade away from 1 MHz, so the attenuation at 10 MHz is -20 dB. Thus the third harmonic power (or level) at the filter output is -80-18-20=-98-20=-118 dBm.
@lokendrasinghlodhi718
11 ай бұрын
@@chembiyant456 Very happy to see your reply! Great explanation, unterstud each and every point. I am a student from IIT But i couldn't get any Analog teachers like you, Althogh I am very interested in this domain but need help! Thank You So Much again!
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