Delay lines are present in a vast majority of the modern electronic circuits. Overlooked and understated, the delay line is one of the building blocks for circuits that are being used in various applications.
Delay lines find their use in fields ranging from fiber optics to acoustics but what exactly are they? Let’s find out:
What are Delay Lines?
Delay line is an electronic component used in circuits to cause the delay of an analog signal. Depending on their application, delay lines can be used in countless different devices. The delay of the analog signal over time allows for versatility and use in a wide range of applications.
Although delay lines are surging into popularity just now, they have been in use for decades now. In fact, delay lines were used in one of the very first computers invented back in 1949.
EDSAC, short for Electronic Delay Storage Automatic Calculator, used delay lines to serve as storage units. Interestingly enough, these delay lines were filled with mercury. Since mercury has an acoustic impedance similar to that of piezoelectric quartz, engineers were successful in reducing energy losses.
Delay lines are of different types based on different parameters. One common classification of delay lines is done on the basis of the signals. Another classification of delay lines is based on delay capabilities.
Types of Delay Lines
There are different types of delay lines based on the nature of signals that these lines delay.
1. Analog Delay Lines
Also known as passive delay lines, analog delay lines are made of analog components. Since analog delay lines comprise of simple electronic components such as inductors and capacitors, they can also attenuate the signal as it moves from input to output.
2. Digital Delay Lines
Known as active delay lines, these are designed only to handle digital signals. In fact, they’re made of digital components and can’t attenuate the signal either. CMOS (Complementary Metal Oxide Semiconductor) is the most common digital delay line.
Delay lines are also classified as fixed delay lines and variable delay lines. Fixed delay lines have a fixed delay time which can’t be changed. Variable delay lines offer the choice of changing the delay time. However, options aren’t infinite although the delay line manufacturers set the limits.
Hopefully, this brief introduction to delay line answers some questions and helps you in deciding which variable delay line to purchase. At ADSANTEC, we pride ourselves in having a large collection of top of the line VDLs.