Why in this circuit
$$V_{out}=\frac{C_1}{C_1+C_2} V_{cc}$$ and not $$V_{out}=\frac{C_2}{C_1+C_2} V_{cc}$$?
The instructor drew also this picture:
but nothing is reported on x-axis and y-axis. Can you help me to understand its meaning? Many thanks
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It only takes a minute to sign up.
Sign up to join this communityWhy in this circuit
$$V_{out}=\frac{C_1}{C_1+C_2} V_{cc}$$ and not $$V_{out}=\frac{C_2}{C_1+C_2} V_{cc}$$?
The instructor drew also this picture:
but nothing is reported on x-axis and y-axis. Can you help me to understand its meaning? Many thanks
simulate this circuit – Schematic created using CircuitLab
Your instructor is right :) Impedance of capacitor is inversely proportional to it's capacitance. $$ V_{out}=V_{cc}\frac{\frac{1}{j\omega C_{2}}}{\frac{1}{j\omega C_{2}}+\frac{1}{j\omega C_{1}}}=V_{cc}\frac{C_{1}}{C_{2}+C_{1}} $$
The picture illustrates transient response of the divider. Verical is Vout and horisontal is time. At the first moment output is determined by C1/C2 ratio, but after long time (after relaxation) it determined only by R1/R2 ratio.
$$ V_o = \frac{\dfrac{1}{C_2}}{\dfrac{1}{C_2} + \dfrac{1}{C_1}} V_{cc}$$