Balance sheetA financial statement that summarizes a company's assets, liabilities and shareholders' equity at a specific point in time. These three balance sheet segments give investors an idea as to what the company owns and owes, as well as the amount invested by the shareholders.The balance sheet must follow the following formula:Assets = Liabilities + Shareholders' EquityIt's called a balance sheet because the two sides balance out

Contracta contract (or informally known as an agreement in some jurisdictions) is an agreement having a lawful object entered into voluntarily by two or more parties, each of whom intends to create one or more legal obligations between them

DiodeAdiodeis an electrical device allowing current to move through it in one direction with far greater ease than in the other. The most common kind of diode in modern circuit design is thesemiconductordiode, although other diode technologies exist. Semiconductor diodes are symbolized in schematic diagrams such as Figurebelow. The term diode is customarily reserved for small signal devices, I 1 A. The termrectifieris used for power devices, I > 1 A.

Semiconductor diode schematic symbol: Arrows indicate the direction of electron current flow.When placed in a simple battery-lamp circuit, the diode will either allow or prevent current through the lamp, depending on the polarity of the applied voltage. (Figurebelow)

Diode operation: (a) Current flow is permitted; the diode is forward biased. (b) Current flow is prohibited; the diode is reversed biased.

clockMost complex digital circuits are sequential, where the logic is performed in discrete steps (such as a computer). A timing pulse signal (called a clock) is used to control the operational steps and keep all the circuitry in proper sequence. (An example of a common clocked circuit element is a flip-flip.) This clock is a digital pulse train and normally operates at a constant high frequency, limited only by the operational speed and propagation delay of the various circuit paths. The clock has to allow enough time for all the circuits to settle to their new state before the next clock arrives.

The clock can be generated by a simple RC relaxation oscillator, or by crystal oscillators if the frequency is critical to maintain an accurate time sequence for the logic outputs.

Thevenin's TheoremAny combination of batteries and resistances with two terminals can be replaced by a singlevoltage sourceeand a single series resistorr. The value ofeis the open circuit voltage at the terminals, and the value ofrisedivided by the current with the terminals short circuited.

Norton's TheoremAny collection of batteries and resistances with two terminals is electrically equivalent to an idealcurrent sourceiin parallel with a single resistorr. The value ofris the same as that in theThevenin equivalentand the currentican be found by dividing the open circuit voltage byr.

Electronics engineering, or electronic engineering, is an engineering discipline which utilizes non-linear and active electrical components (such as electron tubes, and semiconductor devices, especially transistors, diodes and integrated circuits) to design electronic circuits, devices and systems. The discipline typically also designs passive electrical components, usually based on printed circuit boards.