Voltage and lesser-known current sources provide important IC, circuit, and system functions. This section continues the discussion of current sources and related topics. Q: How do you construct a better current source than a voltage source and a resistor? A: There are several ways, but the most common is, ironically, to start with a voltage […]
FAQ
FAQ on voltage and current sources: part 2
Voltage and the lesser-known current sources provide important IC, circuit, and system functions. Current sources We have examined voltage sources, and now we can examine their less-known but necessary complement, the current source. Q: What is a current source? A: As the name implies, the current source is like a voltage source but different. It […]
FAQ on voltage and current sources: part 1
Voltage and the lesser-known current sources provide critical IC, circuit, and system functions. Voltage sources and their complement to current sources are essential elements of many systems, circuits, and IC designs. Experimenters and novice engineers are familiar with voltage sources of various types — even if not by that name — in the form of […]
FAQ on pull-up/pull-down resistors: part 2
Even this relatively simple circuit arrangement has subtleties that affect performance. Part 1 explored the role of pull-up and pull-down resistors to ensure that the binary (digital) circuit points are at an unambiguous 1 or 0 level. This part explores basic issues of sourcing, sinking current, and resistor sizing. Sourcing and sinking current Q: What […]
FAQ on pull-up/pull-down resistors: part 1
Even this relatively simple circuit arrangement has subtleties that affect performance. In the crisp, clean, theoretical binary world, signals exist in only two unambiguous states, generally called 1 and 0 (one and zero). However, when engineering students, hobbyists, and digital-only professionals get into the hands-on real world of circuits and systems, they find that binary […]
Selection and implementation of BLDC control strategy
By Shao Zhang, Qorvo Understanding the differences between trapezoidal, sinusoidal, and field-oriented control can help engineers understand the value of Field Oriented Control (FOC) and the choices available to optimize their designs. BLDC motors can be smaller, lighter, and quieter than traditional brushed DC motors while enhancing the reliability and energy efficiency of consumer, industrial, […]
How do SiC and GaN devices age?
By Peter Friedrichs, Infineon Technologies SiC and GaN devices operate at higher stress levels than silicon devices. The semiconductor and automotive industries have strict qualification tests for that. Silicon carbide (SiC) and gallium nitride (GaN) wide bandgap (WBG) technologies are well known for their performance advantages over silicon (Si) in many high-power areas, including their […]
Add gas discharge tubes to your circuit-protection device roster
GDTs are circuit-board-compatible overvoltage-protection devices and are far removed from the “spark gap” of monster movies. Circuit protection is like insurance: you really don’t need it until you unexpectedly do, and then you’re very glad you have it. This protection falls into two broad categories: protection against overcurrent (the common thermal fuse is the first […]
What are the current sensing challenges with WBG power converters?
The high-frequency switching of WBGs presents challenges related to bandwidth and speed that can be addressed with new sensing techniques. In addition, gallium nitride (GaN) and silicon carbide (SiC) devices have different tolerances to short circuit conditions and requirements for current sensing. Current sensors with the bandwidth needed to capture ultra-fast short-circuit events can be […]
What is a power quality survey used for?
Power quality (PQ) surveys are used in data centers, hospitals, and industrial installations to improve uptime and equipment performance by identifying the root causes of power quality problems. When discussing PQ problems, three important considerations are the types of PQ problems, the sources of PQ problems, and the tools for identifying and measuring PQ problems. […]