Solid state isolators (SSIs) can be an effective tool for providing isolation for programmable logic controllers (PLCs). When using SSIs in PLCs, several important considerations come into play to ensure optimal performance, reliability, and safety. This article briefly reviews the applications for SSIs in PLCs, looks at safety system architecture options, and reviews the technology […]
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What are the performance standards for solid state isolators?
Solid state isolators (SSIs) use coreless transformers (CTs) to provide electrical isolation between circuits while supporting power and signal connections. Isolation supports safety, noise immunity, reliability, and other performance benefits. This article briefly compares SSIs with alternative technologies used in solid state relays (SSRs) and reviews international standards for operating lifetime and isolation performance. Some […]
What are the advantages of solid-state isolators compared with optical SSRs?
Optically isolated solid-state relays (SSRs) (also called optocouplers or photovoltaic relays) were developed to overcome some of the performance limitations of electromechanical relays. While they can support a larger number of switching cycles, the LED in an optical SSR degrades over time, ultimately limiting the lifetime of the device. Capacitive and inductive-based isolation technologies were […]
What is a coreless transformer and how does it work in a solid-state isolator?
Coreless transformers (CTs) in solid state isolators (SSIs) rely on inductive coupling to transfer information and power across an isolation barrier. CTs employ near-field magnetic induction coupling, which is used in some wireless charging protocols. Simple induction coupling relies on the proximity of the coils for optimal efficiency and is less efficient as the separation […]
How can lasers be used to cool integrated circuits?
Lasers are often used for heating materials, but they can also be harnessed for localized cooling of ICs. Laser cooling works by using the momentum of photons to slow down atoms. It’s used in cryogenic coolers for applications like quantum computing, and this principle is being adapted for cooling ICs. Laser cooling is a two-step […]
What is the IEEE 1801-2024 Unified Power Format 4.0 standard?
IEEE Unified Power Format (UPF) 4.0 is a standard specification language that defines the low-power architecture of low-power ASICs. It’s designed to streamline integration throughout the design, verification, and implementation process, with a focus on power intent for energy-aware electronic system design. UPF is built using the Tool Command Language (TCL) and complements hardware description […]
Gate drivers — the critical link in power-device performance: part 3
This section will discuss some of the many subtleties of the gate driver and its power source. Other gate-driver converter considerations Gate-driver dc-dc converters have other unique issues. Among them are: 1) Regulation: the load on the dc-dc converter is close to zero when the device is not switching. However, most conventional converters require a […]
Gate drivers — the critical link in power-device performance: part 2
Thus far, we have examined the general issue of power devices and their characteristics. This part goes into the details of the power-device gate driver. Gate-drive details To drive current into the gate, the positive rail’s voltage should be high enough to ensure full saturation/enhancement of the power switch, but without exceeding the absolute maximum […]
Robust design for Variable Frequency Drives and starters
Variable Frequency Drives (VFDs) and soft starters are essential components in modern industrial and commercial systems. VFDs provide precise control over motor speed, torque, and efficiency, matching speed to load requirements to minimize energy consumption. Soft starters gradually increase motor voltage to limit inrush current and prevent damage to the electrical system. Controlled inrush current […]
Gate drivers — the critical link in power-device performance: part 1
Effective MOSFET/IGBT-device switching depends on the gate driver and its power supply. From power supplies and motor drives to charging stations and myriad other applications, switching power semiconductors such as silicon (Si), silicon carbide (SiC), and gallium nitride (GaN) MOSFETs, as well as insulated-gate bipolar transistors (IGBTs), are the key to efficient power-system designs. However, […]
