Glossary Definition for Mixed-signal

Glossary Term: Mixed-signal 


Mixed-signal ICs are integrated circuits that contain both analog and digital circuitry on one chip. An analog signal is a continuous time-varying signal, and a digital signal is a noncontinuous signal that takes on only a finite number of values. Mixed signal ICs make use of both of these types of signals. Mixed-signal ICs are used in a wide variety of applications and application-specific integrated circuits (ASICs).

Analog signals

As an example, a building block of analog circuit design is the op amp, which is a high-gain amplifier. An op amp can take a continuous signal and output another, higher-valued, continuous signal. An op amp can also be used to make a comparator, which is a circuit that compares two input voltages and outputs a binary signal indicating which is larger. Since the output of the comparator is digital, this is an example of a mixed-signal circuit.

Digital signals

Where analog signals are continuous, digital signals are discrete, meaning that they take on a finite number of values. An example is a square wave, where a signal alternates between values in steps, ideally instantaneously. Another example is a binary signal, which can have two possible values (such as 0/1 or on/off) and is used in logic gates such as AND/NAND gates or in D flip flops.

ADCs and DACs

The two clearest examples of mixed-signal ICs are analog to digital converters (ADCs) and digital to analog converters (DACs). Since these convert analog to digital or digital to analog, they must contain circuitry for both.

Find a term alphabetically: