From Op-Amps to Analog Systems
An op-amp is a building block rather than an end point. Once it is understood, many other analog ICs become easier to understand because they contain similar differential stages, gain stages, references, and output structures.
Comparators
A comparator resembles an op-amp input stage but is designed for rapid open-loop switching rather than linear feedback.
Instrumentation amplifiers
These combine high input impedance, differential gain, and matched internal resistors for excellent common-mode rejection.
Voltage references
References create stable voltages that change very little with supply, load, temperature, and time.
Linear regulators
A regulator combines a reference, error amplifier, feedback network, and power pass device.
Timers and oscillators
The 555 timer combines comparators, a resistor divider, latch, discharge transistor, and output stage—a fine example of analog and digital functions living together.
ADCs and DACs
Converters connect analog signals to digital processing. Their internal circuits use amplifiers, comparators, references, switches, resistor or capacitor networks, and digital logic.
Audio and sensor ICs
Modern devices may integrate preamplifiers, filters, converters, calibration memory, communication interfaces, and protection around the same analog core ideas.