Electronics/Scratch pad

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Parts list and theory[edit]

Voltage = potential between two charges. Defined as the derivative of the flux linkage:

V(t)=\frac{d(Ni(t))}{dt}

Current = flow of electrons Defined as the rate of change of the charge:

I(t)=\frac{dQ(t)}{dt}

There are 3 parameters in an electrical circuit:

Resistance =

R=\frac{V}{I}

In a resistor voltage and current are in sync.

V(t)=Ri(t)

In capacitors voltage leads current. Capacitors are good as a low pass filter.

V(t)=\frac{1}{C} \int i(t)dt

In inductors current leads voltage. Current equals the negative derivative of the voltage. Inductors are good as a high pass filter.

V(t)=L\frac{di(t)}{dt}

relationship between voltage and current

P=VI

in a circuit

in series voltage drops and current stays constant in parallel voltage stays constant and current divides according to the resistance

voltage stays constant in parallel and current drops in p

pizoelectric = a crystal under compression creates current

transformers

vacuum tube = electron emitter in a vacuum

integrated circuit a semiconductor doped with impurities

group 4 elements doped with group 3 and 5

electrons and holes

ground

applications[edit]

Resistors in series (Christmas lights, stove)

computer

3.5, 5, 12 Volts

lamp

monitor

power distribution (three phase power)

radio

modem

speaker

circuit design[edit]

bandgap

cmos

flip flop

computer parts

leakage current