Skip to main content

Nodal Analysis

The nodal analysis and the mesh analysis are based on the systematic application of Kirchhoff’s laws.


Nodal analysis is a method that provides a general procedure for analyzing circuits using node voltages as the circuit variables. Having ‘n’ nodes there will be ‘n-1’ simultaneous equations to solve.


The procedure for analyzing a circuit with the node Analysis:




  1. Identify all nodes of the circuit.

  2. Select a node as the reference node also called the ground and assign to it a potential of 0 Volts. All other voltages in the circuit are measured with respect to the reference node.


for example in the below circuit nodes are Va,Vb and Vc with respect to reference       node D. nodal1


According to Kirchhoff's current law  we have  I1 + I2 = I3   and  I=V/R from ohm's law.


   so we have  I1 = (Va - Vb)/10 ;   I2 = (Vc - Vb)/20 ;   I3 = (Vb)/40


nodal 2.gif


As Va = 10v and Vc = 20v , Vb can be easily found by:


nodal 3

 

Comments

Post a Comment

Popular posts from this blog

photodiode

Introduction : A photo diode is a semi-conductor device, with a p-n junction and an intrinsic layer between p and n layers. It can be used as a light detector, which involves the conversion of light into current or voltage depending on mode of operation. [gallery ids="867,866" type="rectangular"] construction :   Working : When a photon of sufficient energy strikes the diode, it creates an electron-hole pair. This mechanism is also known as the inner photoelectric effect. If it occurs at the junction these carriers are swept from the junction by the built-in electric field of the depletion region. Thus holes move toward the anode, and electrons toward the cathode, and a photo current is produced. The total current through the photo diode is the sum of the dark current (current that is generated in the absence of light) and the photo current, so the dark current must be minimized to maximize the sensitivity of the device. Mainly it is operated in two modes 1.  Photo ...

voltage

Voltage, is is the difference in potential between two points  in an electric field. also called electromotive force. voltage is the   pressure from an electrical circuit’s power source that pushes charged electrons (current).           grater the voltage grater the flow of electric current. Voltage is symbolized by   V or E . The standard unit is the volt. One volt will drive one columb  (6.24 x 10 18 ) charge.such as electronics through a resistance of one ohm. Voltage can be direct or alternating. A direct voltage maintains the same polarity. In an alternating voltage, the polarity reverses direction periodically. The number of complete cycles per second is the frequency which is measured in hertz.

BJT (bipolar junction transistor)

A bipolar junction transistor is a three terminal semiconductor current controlled device with two P-N junctions. The three terminals are emitter(E), base(B) and collector(C). the emitter junction is heavily doped, base is less doped and made very thin and collector terminal is moderately doped. Collector has grater size than emitter and base terminal is thinner than both. (The thinner the base, the stronger the E-C electric field, and the larger the impact of a small current injected into the base. Explained clearly in active mode operation below) emitter terminal is moderate in size. A BJT has two types of transistors: NPN transistor PNP transistor NPN transistor : In an NPN transistor a p-type material is sandwiched between two n-type materials. [gallery ids="979,978" type="rectangular"] PNP transistor : In a PNP transistor a n-type material is sandwiched between two p-type materials. [gallery ids="989,990" type="rectangular"] Oper...