An electronic circuit is a closed path or paths formed by the interconnection of electronic components through which an electric current can flow. Physically, an electronic circuit can be as small as a pin point or cover many miles. They are constructed by connecting electronic components together with conductors, which allow electricity to flow between the components. Integrated circuits are small circuits constructed from a piece of semiconductor housed in a protective package. While larger circuits may be built by assembling electronic components onto a printed circuit board (PCB), which is used to mechanically support and electrically connect the components. Integrated circuits are typically used as components in larger circuits built onto PCBs. When components are connected using wire as the conductor, the circuit may be extended to cover or connect a large area. Breadboards, perfboards or stripboards are common for testing new designs. They allow the designer to make quick changes to the circuit during development.
Series combination of resistors: The equivalent resistance is R =
R1 + R2 +
Parallel combination of resistors: If R1, R2, are connected in
parallel, the equivalent resistance R is such that 1/R = 1/R1 + 1/R2 +
RC circuit: Connect a battery with emf E, a resistor with
resistance R, and a capacitor with capacitance C, and a switch. When the switch is open, no charge flows and the
capacitor remains uncharged. If the switch is closed at time t = 0, the capacitor begins charging. The charge on
the capacitor, as a function of time t, is given by Q = CE [1 exp(-t / RC)]. The product RC has the
units of time and is called the time constant of the RC circuit.
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.