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Design of a single non-inverting op-amp amplifier with a voltage gain of 25 dB.

i. Draw the circuit schematic and calculate possible resistor values.

ii. If an input signal with a frequency of 100 kHz, a peak to peak voltage of 200 mV and a DC offset of 1 V should be applied to this amplifier, calculate the minimum gain-bandwidth product, and the minimum slew rate of the op-amp (assume the supply voltage to be sufficiently large).

User Immutable
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i. Circuit Schematic:

```
+Vin -----R1-----+--------- Output
|
-Vin ---R2-----| |
|
Rf
|
-Vcc
```

To design a non-inverting op-amp amplifier with a voltage gain of 25 dB, we can use the following formula:

Voltage Gain (Av) = 1 + (Rf/R1)

Since the desired voltage gain is 25 dB, we can convert it to a linear gain as follows:

Av (linear) = 10^(25/20) = 18.7

Now, let's assume a value for R1. We can choose a common value, such as R1 = 10 kΩ.

Substituting the values into the voltage gain formula, we can solve for Rf:

18.7 = 1 + (Rf/10kΩ)
Rf = 18.7 * 10kΩ - 10kΩ = 187kΩ - 10kΩ = 177kΩ

Therefore, we can use R1 = 10 kΩ and Rf = 177 kΩ for the desired voltage gain of 25 dB.

For the input signal with a frequency of 100 kHz, a peak-to-peak voltage of 200 mV, and a DC offset of 1 V, the op-amp needs to have a gain-bandwidth product (GBW) and slew rate (SR) that can handle the signal faithfully without distortion.

The minimum gain-bandwidth product can be calculated using the formula:

GBW = Av * f

Where Av is the voltage gain and f is the frequency.

GBW = 18.7 * 100 kHz = 1.87 MHz

So, the minimum gain-bandwidth product required is 1.87 MHz.

The minimum slew rate (SR) can be calculated using the formula:

SR = 2π * f * Vpp

Where f is the frequency and Vpp is the peak-to-peak voltage.

SR = 2π * 100 kHz * 200 mV = 125.66 V/μs

Therefore, the minimum slew rate required is 125.66 V/μs.

To design a non-inverting op-amp amplifier with a voltage gain of 25 dB, we can use resistor values of R1 = 10 kΩ and Rf = 177 kΩ. The op-amp should have a minimum gain-bandwidth product of 1.87 MHz and a minimum slew rate of 125.66 V/μs to handle an input signal with a frequency of 100 kHz, a peak-to-peak voltage of 200 mV, and a DC offset of 1 V.

User Xiaofan
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