Engineering How to Design a Circuit from a Given Transfer Function?

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The discussion focuses on designing a circuit based on the transfer function T(s)=50000s/((s+50)(s+1000)). The user initially struggles with translating the transfer function into a circuit using op-amps, resistors, capacitors, and inductors, noting that the time domain representation resembles a capacitor discharging. Key suggestions include familiarizing oneself with the transfer functions of simple RC filters and using op-amps as buffers to prevent interference between filter stages. The user successfully separates the transfer function into two systems, H1 and H2, and confirms that this approach helps in circuit design. Ultimately, the user expresses gratitude for the guidance received, indicating progress in their design process.
Lancelot59
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I'm given the following transfer function:
T(s)=\frac{50000s}{(s+50)(s+1000)}
and I need to constuct a circuit from it using opamps, resistors, capacitors, and inductors. Capacitors must be 100nF.

I'm not quite sure how to start here. I managed to get a time domain version of the transfer function:
T(t)=\frac{-50000}{19}e^{-50t}+\frac{100000}{19}e^{-1000t}

The problem is I have no idea how to get started. I know that the time function looks like a capacitor discharging, however I don't know how to start going about turning this function into a circuit.
 
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You should familiarize yourself with the transfer functions of the simple RC filters (low pass and high pass).

hint: An op-amp can be used as a buffer between filter stages (keeps them from interfering with each others corner frequencies and gains).
 
gneill said:
You should familiarize yourself with the transfer functions of the simple RC filters (low pass and high pass).

hint: An op-amp can be used as a buffer between filter stages (keeps them from interfering with each others corner frequencies and gains).

Ah, I see. So I can separate it into two systems with the following characteristics:

H_{1}=\frac{50000}{s+50} H_{2}=\frac{s}{s+1000}

and buffer them together?
 
Lancelot59 said:
Ah, I see. So I can separate it into two systems with the following characteristics:

H_{1}=\frac{50000}{s+50} H_{2}=\frac{s}{s+1000}

and buffer them together?

Yes, you could.
 
Or I could interchange the numerators. Either way this puts me on a better track, I'll see what I can come up with.
 
I managed to solve it! Thanks for pointing me in the right direction.
 

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