The schematic symbol for an ideal op-amp is provided in Figure 6.1.1, where \(V_-\) and \(V_+\) are called the inverting input and non-inverting input respectively. The amplifier output is given as \(V_\text{out}\text{.}\) Op-amps require an external voltage source for operation, just as transistors require \(V_{CC}\) and \(V_{EE}\) as supply voltages. These two supply voltages are marked as \(V_{s+}\) and \(V_{s-}\text{,}\) though these connections are sometimes left out in circuit diagrams.
Figure6.1.1.Schematic symbol for an ideal op-amp. The inverting and non-inverting inputs are specified as \(V_-\) and \(V_+\text{.}\) The two voltages \(V_{s+}\) and \(V_{s-}\) are supplied by an external power source.
Figure 6.1.2 shows a top-view pin diagram for two general-purpose op-amps. The half-moon shape allows one to identify pin 1, with remaining pins being counted in a counter-clockwise manner.
Figure6.1.2.Sample top-view pin diagrams for two general-purpose op-amp chips, the LM741 and the LM358. This particular pin diagram is specific to the general purpose LM741 op-amp chip. Other op-amp chips may have different pin diagrams.
