# Electronics/Electronics Formulas/Electronics Components

## Electronics Components

### Resistor

Resistor Characteristics
Function To reduce current
Construction Resistor is made from a straight line Conductor of Dimension
Length, l
Area, A
Resistivity, ρ
Symbol
Resistance $R = \frac{V}{I} = \frac{1}{\rho} \frac{A}{l}$
Voltage $V_R = I R$
Current $I_R = \frac{V}{I}$
Power $P_R = V_R I_R = I^2 R = \frac{V^2}{R}$
NOTE : This is electric energy loss as Heat
Resistance Resistance and temperature Resistance and Electric Energy Loss
R R = Ro (1+nT) . For Conductor
R = Ro enT For Semi Conductor
Electric Energy Delivered (P) = Electric Energy Supply (Pv)- Electric Energy Loss (Pr)
$P = P_v - P_r$
$P = VI - I^2 R = I(V - IR)$
$P = VI - \frac{V^2}{R}= V(I - \frac{V}{R})$

### Capacitor

Capacitor Characteristics
Function To store Energy in the form of Electric Field
Construction Capacitor is made from a 2 parallel conductor plates separated by a non conduct dielectric of Dimension
Length, l
Area, A
Dieletric constant, ϵ
Symbol
Capacitance $C = \frac{Q}{V}$ = ϵ $\frac{A}{l}$
Voltage $V_C = \frac{1}{C} \int I dt$
Current $I_C = C \frac{dV}{dt}$
Power $P_C = \frac{1}{2} C V^2$
Reactance $X_C = -\frac{1}{\omega C}$
Impedance $Z_C = \frac{1}{j\omega C} = \frac{1}{sC} = jX_C$

### Inductor

Inductor Characteristics
Construction inductor is made from a straight wire conductor with several turns of Dimension
Length, l
Area, A
Number of Turns, N
Permitivity, µ
Symbol
Inductance $L = \frac{B}{I}$ = µ $N^2 \frac{l}{A}$
Voltage $V_L = L \frac{dI}{dt}$
Current $I_L = \frac{1}{L} \int V dt$
Power $P_L = \frac{1}{2} L I^2$
Reactance $X_L = \omega L$
Impedance $Z_L = j\omega L = sL = jX_L$

### Transformer

Transformer Characteristics
Symbol
$\frac{V_S}{V_P}$ $\frac{V_S}{V_P} = \frac{N_S}{N_P}$

### Diode

Diode Characteristics
Construction Diode is made by joining Positive-typed Semi Conductor with a Negative-Typed Semi Conductor
+ o--[P][N]--o -
Symbol
I - V Curve
Vd (I = 1 mA) 0.6v for Si
0.3v for Si
Conduction V < Vd . I = 0 . Non Conduct
V = Vd . I = 1mA . Start Conduct
V > Vd . $I = I_se^\frac{V_d}{V_t} t$ . Conduct
Polarities Connect Source and Diode in the same polarities. Diode conducts
Connect Source and Diode in the reverse polarities. Diode does not conduct
Current Flow's Direction When diode conducts, current flows in the direction of the arrow

### Transistor

Transistor Characteristics
Construction + o--[P][N][P]--o - Connect one Negative-Typed Semi Conductor in between two two Positive-Typed Semi Conductors
- o--[N][P][N]--o + Connect one Positive-Typed Semi Conductor in between two two Negative-Typed Semi Conductors
Symbol
I - V Curve
Vd (I = 1 mA) 0.6v for Si
0.3v for Si
Conduction V < Vd . I = 0 . Non Conduct
V = Vd . I = 1mA . Start Conduct
V > Vd . $I = I_se^\frac{V_d}{V_t} t$ . Conduct
Polarities Connect Source and Diode in the same polarities. Diode conducts
Connect Source and Diode in the reverse polarities. Diode does not conduct
Current Flow's Direction When diode conducts, current flows in the direction of the arrow

### Op Amp

Operation Amplifier Characteristics
IC 747 The main function of Op Amp 747 is to amplify the difference of two input voltages
Symbol
1 Chỉnh Không
2 Chân Nhập Trừ
3 Chân Nhập Cộng
4 Chân Điện Nguồn -V
5 Không Dùng
6 Chân Xuất
7 Chân Điện Nguồn +V
8 Không Dùng
Operation Formulas Amplify the difference of 2 input voltages, $V_o = A ( V_+ - V_- )$
Inverting Amplifier, $V_o = - A V_-$
Non Inverting Amplifier, $V_o = A V_+$
Voltage Comparator
$V_- = V_ + , V_o = 0$
$V_- > V_ + , V_o = V_s-$
$V_- < V_ + , V_o = V_s+$