Temperature effects on resistance. Resistance Variation with Temperature.

The value of the resistance of a material varies with temperature change. For this reason, the circuit or system containing these elements should work in controled environment

Energy and Electric power.

Power is the speed at which work is done.

Electric power is the multiplication of the current (amps) by the voltage (volts). P = I x V.

What is a Resistor?

A Resistor is an electrical element that causes opposition to the flow of the electric current.  Using the Ohm’s Law V = IxR we can find the voltage on the resistors terminals.

What is a Truth Table?

The Truth Table is used to simplify boolean equations obtained from digital circuits. The truth tables can have many columns, but all tables operate in the same way.

Definition of inductance

An inductor has the property to oppose any change in the current passing through it.

This property is called inductance. When a current flows through a conductor, a magnetic field is created.

Ohm’s Law relates in one equation the voltage, the current and resistance. Resistance = Resistor’s value.

A more complete expression of Ohm’s Law is achieved using the electric power formula

Zener diode Voltage regulator calcutation

A Zener diode Voltage regulator calcutation is made using a simple circuit of a resistor /Rs) and a Zener diode (Z).

This two elements values and characteristics are obtained using special formulas

JK Flip-Flop – PRESET & CLEAR Inputs – Truth Table

The JK Flip-Flop is a sequential device with 3 inputs (J, K, CLK (clock signal)) and 2 outputs (Q and Q’). J and K are control inputs.

What is a wirewound resistor?

A Wirewound resistor is a resistor made with a conductive wire of a high resistivity. This wire is made of a special alloy and it is wound on a support tube of refractory material such as ceramics, porcelain, etc.

Transformerless Power Supply Circuit We will use a zener diode among other elements to acheive the Transformerless Power Supply circuit. This  means that our power supply will give a limited range current value (it will be a maximum and a minimum posible current that the power supply circuit can deliver). This power suply must be permanently connected to the circuit as a whole unit. […]

NAND gate using transistors

This NAND gate using transistors circuit simulates the operation of a two or more inputs NAND gate. (There is a diode for each input. D1, D2, …)

TRIAC. Power control on alternating current (AC)

Triac is a semiconductor device that belongs to the family of thyristor control devices. It is essentially two SCR connected in parallel and backwards, sharing the same gate.