Selecting Passive Components

5.1 Selecting Passive Components

We use passive components to conduct current linearly—at least to a first-order approximation—with respect to:

• Voltage.

• Time.

• Frequency.

Resistors (Chapter 6) consist of long, skinny conductors, usually supported by insulators. In the time domain,

where:

• i(t) is the current flowing through the resistor, in amperes.

• v(t) is the voltage across the resistor, in volts.

• R is the resistance in ohms.

Fuses (Chapter 7) are low-value resistors that are designed to open if too much current is forced through them.

Capacitors (Chapter 8) consist of two or more parallel or concentric plates separated by an insulator. Capacitors store energy in the electric field between the plates. In the time domain:

where:

• i(t) is the current flowing through capacitor, in amperes.

• C is the capacitance in farads.

• v(t) is the voltage across the capacitor, in volts.

• t is the time in seconds.

Inductors (Chapter 9) consist of conductors coiled in a helix or spiral, in one or more...