Capacitance for a parallel RC circuit

Click For Summary
SUMMARY

The discussion centers on calculating the values of the resistor and capacitor in a parallel RC circuit with a Zener diode, maintaining a voltage of 4.7V and a power of 5mW. The resistance was determined to be 4.4k Ohms using the formula P=V^2/R. The challenge lies in calculating the capacitance, where the user derived two equations: Ic=CdV/dt and Ir=V/R, but requires further guidance on solving for capacitance. Additional context about the circuit's connection to a rectifier is also sought.

PREREQUISITES
  • Understanding of Ohm's Law and power calculations
  • Familiarity with capacitor charging equations
  • Knowledge of Zener diode operation
  • Basic principles of AC circuits and rectification
NEXT STEPS
  • Study the relationship between current and capacitance in RC circuits
  • Learn about Zener diode voltage regulation techniques
  • Explore the effects of frequency on capacitor behavior in AC circuits
  • Investigate full-wave and half-wave rectification impacts on circuit performance
USEFUL FOR

Electrical engineering students, hobbyists designing RC circuits, and anyone involved in power supply design and analysis.

envanyatar
Messages
15
Reaction score
0

Homework Statement



A circuit consists of a Zener diode, capacitor and resistor in parallel. Voltage to be maintained across the components is 4.7V, power 5mW. Find the values for resistor and capacitor

Homework Equations



(Below)

The Attempt at a Solution



I found the resistance by taking P=V^2/R, and using the given values for P and V, R=4.4k(Ohms). I have a problem with finding the capacitance value.
I found the current for the resistor. But there're 2 unknowns now, the capacitor value and the Ic. I've come up to the point where two equations are obtained: Ic=CdV/dt; Ir=V/R. How do I proceed from here to get C? Is this the correct way of approaching this?

Thanks.
 
Physics news on Phys.org
The problem is incomplete. Is this circuit connected to the output of a rectifier? If so, is it full wave or half wave? What is the peak voltage of the rectified voltage. (I assume the frequency is 60 Hz).
 

Similar threads

Calculating Current in a Series RC Circuit
  • · Replies 4 ·
Replies
4
Views
3K
Engineering Step response of RC circuit with independent voltage and current sources
  • · Replies 7 ·
Replies
7
Views
3K
Equivalent resistance with a capacitor
  • · Replies 11 ·
Replies
11
Views
8K
Engineering Why are the voltages calculated in this way? (CE BJT Amp circuit)
  • · Replies 8 ·
Replies
8
Views
2K
Engineering Solve 2 Loop RC Circuit: Find Q(topen)
  • · Replies 8 ·
Replies
8
Views
4K
Engineering Transient RC Circuit (got answer in s but not in t-domain)
  • · Replies 2 ·
Replies
2
Views
2K
Engineering Impedance angle in RL and RC circuits
  • · Replies 4 ·
Replies
4
Views
2K
Engineering Simplifying a series / parallel circuit and calculating unknown values
  • · Replies 3 ·
Replies
3
Views
2K
Engineering Circuit theory: capacitor energy storage and discharging/charging times?
  • · Replies 10 ·
Replies
10
Views
3K
What is the Voltage on C1/C2 after the switch closes?
  • · Replies 11 ·
Replies
11
Views
3K