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9th December 2019, 19:35 #1
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Bilinear switched capacitor resistor equivalent resistance
I am trying to find the equivalent resistance of the following circuit in baker's book.
How do you get the factor of 4 in the denominator? I am trying to get the answer by using the principle of transfer of charge and conservation of charge like in the case below:
https://en.wikipedia.org/wiki/Switch...citor_resistor
we can assume that the voltage on the left side of cap is Vin and on the right Vout.
during phi1 voltage across the cap is V1V2 and during phi2 voltage across cap is V2V1. So shouldn't delta q be 2C(V1V2)?
so shouldn't the answer be 1/2Cf ?

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9th December 2019, 23:47 #2
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Re: Bilinear switched capacitor resistor equivalent resistance
The capacitor is charging from ΔV to +ΔV in phase 1 and back in phase 2, total q = 4CΔV.

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10th December 2019, 01:51 #3
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Re: Bilinear switched capacitor resistor equivalent resistance
This is not clear.
Let say the voltage at left side is V1 and on the right V2.
When s1 is closed the voltage across C is V1V2. The charge of C is C(V1V2). Now s1 is opened and s2 is closed. The voltage across C is V2V1 and the charge on it is C(V2V1). So the charge transferred out of the capacitor should be C (V1V2)  C (V2V1) is 2C(V1V2). Why is this quantity 2C(V1V2) multiplied by 2 again?

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10th December 2019, 10:01 #4
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Re: Bilinear switched capacitor resistor equivalent resistance
Charge is transferred to the output also when s1 is closed. What you describe happens 2 times per clock cycle.
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11th December 2019, 00:42 #5
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