There are three main technologies used for digital isolators, capacitive, magnetic, and giant magnetoresistive (GMR). This FAQ briefly looks at capacitive designs (they are covered in more detail in “What is a capacitive digital isolator”), then digs deeper into magnetic and GMR devices. Capacitive digital isolators use two CMOS dies connected with a capacitive isolation […]
What’s quantum control and how is it used?
Quantum control has several uses. Its primary use is to prevent the performance degradation of quantum computers as a result of the decoherence of qubits. It’s also an important function in the field of quantum sensing; for information on that application, see the FAQ on “What’s a quantum sensor?” This FAQ reviews the current status […]
What inductor characteristics are needed for PoDL in Single-Pair Ethernet?
Basic Single-Pair Ethernet (SPE) requires at least a common mode inductor (CMI). When power over data line (PoDL) functionality is added, so is a differential mode inductor (DMI) and sometimes an isolation transformer. These magnetic elements interact and can reduce SPE performance. Correctly specifying them is important to ensure efficient operation and reliable data transfer. […]
What are the key specifications of digital isolators? Part 2
Digital isolators have two primary functions, to provide isolation and to transmit information across the isolation barrier. Part one looked at the various specifications related to voltage and isolation performance. Part two details key specifications related to the transmission of information. Common‐mode transient immunity (CMTI) is one of three key specifications of digital isolators. The […]
What are the key specifications of digital isolators? Part 1
Digital isolators have two primary functions, to provide isolation and to transmit information across the isolation barrier. This first of two FAQs on digital isolator specifications looks at voltage and isolation specs. Part two details key specifications related to information transmission. Two basic voltage specs are: Working voltage (VIOWM) is the maximum rms, or corresponding […]
What’s the difference between an SPE isolation inductor and a transformer?
Single-pair Ethernet (SPE) isolation inductors and transformers are available in several configurations. They are used in applications where simple capacitive isolation is not sufficient. There are two types of SPE isolation transformers, simple chip transformer designs and so-called case transformers that can combine the functions of isolation with common mode rejection. This FAQ looks at […]
What is a capacitive digital isolator?
Capacitive digital isolators consist of two digital CMOS dies connected with a capacitive isolation barrier. The barrier provides galvanic isolation to meet safety regulations, reduce noise from ground loops, and connect interface communication boards or subcircuits that operate with different supply voltages. They are used in power converters and motor drives, electric vehicles (EVs), consumer […]
What’s a quantum sensor?
Quantum sensing is important in the control of quantum computers and in advanced sensor applications ranging from navigation to medical diagnosis. For a discussion of quantum control, check out the FAQ “What’s quantum control and how is it used?” This FAQ looks at how quantum sensing is used to measure various physical parameters and efforts […]
How many types of radar are there?
Radio detection and ranging (radar) uses reflected radio waves to detect and determine the distance, angle, and velocity of objects relative to the radar system. A basic radar system consists of a transmitter producing electromagnetic waves in the radio or microwave spectrum (these can be pulsed or continuous), a transmitting antenna, a receiving antenna (often […]
How to specify differential mode inductors for Single-Pair Ethernet?
Differential mode inductors (DMIs) are important components for power over data line (PoDL) and the related single pair power over Ethernet (SPoE) standards. This FAQ begins with a review of where DMIs fit into single-pair Ethernet (SPE), then compares PoDL and SPoE implementations and application targets. Coupling and decoupling DMIs play an important role in […]