By Cyrielle Marjolaine. Power. Publised at Tuesday, December 19th 2017, 11:49:21 AM. In some applications, a regulator may spend most of its life shut off (in standby mode) and only supply load current when a main regulator fails. In these cases, the quiescent current determines the battery life.
By Valentine Sybille. Amplifier. Published at Monday, December 25th 2017, 05:18:44 AM. Unfortunately we are not quite done yet. I mentioned the concept of a ground loop earlier. This is a particularly insidious problem that can easily ruin a good project. In very general terms it is formed whenever there are multiple signal ground paths to the same termination. I can be internal or external to the piece of equipment. The most frequent result is a hum that either will not go away or happens only when something is connected to the piece of equipment. I need now to provide a few brief words about hum. If the hum is at the same frequency as the AC mains (either 50 or 60 Hz typically) then it is likely from interconnections external to the equipment or poor shielding internal to the equipment. If the hum is at twice the mains frequency then it nearly always because of inadequate power supply filtering. Ground loops are usually at the mains frequency. So if you encounter one, then you must search for the alternate ground paths that relate to the signal chain. If it external (occurs only when the equipment is attached to an external item), then check for things like phonograph grounding at the phonograph end. As an example I have seen is when one terminal of a cartridge connected to the ground in the tone arm (OK and fairly common) and a separate ground from the same tone arm (not OK) is provided for connection to the amplifier chassis ground (this is not to be confused to the situation when there is a separate ground wire from the phonograph chassis that has no connection to the ground in the cartridge). Since both the signal ground and tone arm ground are connected at the phonograph they will form a ground loop (between the shields and ground wire) when connected to the amplifier. The solution in such cases is to separate the grounds at the phonograph. An internal example was mentioned earlier when both ends of internal shielded cables are joined in two different places (at the input jacks and volume control). The irony of the situation and part of the insidious nature of ground loops is that they can on occasion be benign and not cause hum. They can later show up when a new piece of equipment is attached to the system. In all cases however, they have the same fundamental cause, alternate paths for the signal return.
By Alix Loane. Diagram. Published at Monday, December 25th 2017, 03:55:15 AM. In a digital circuit, power supply voltage levels are constrained to two distinct values – “logic high voltage” (called LHV or Vdd) and “logic low voltage” (called LLV or GND). The GND node in any circuit is the universal reference voltage against which all other voltages are measured (in modern digital circuits, GND is typically the lowest voltage in the circuit). In a schematic, it is often difficult to show lines connecting all GND nodes; rather, any nodes labeled GND are assumed to be connected into the same node. Often, a downward pointing triangle symbol, is attached to a GND node in addition to (or instead of) the GND label. The Vdd node in a digital circuit is typically the highest voltage, and all nodes labeled Vdd are tied together into the same node. Vdd may be thought of as the “source” of positive charges in a circuit, and GND may be thought of as the “source” of negative charges in a circuit. In modern digital systems, Vdd and GND are separated by anywhere from 1 to 5 volts. Older or inexpensive circuits typically use 5 volts, while newer circuits use 1-3 volts.
By Alix Loane. Circuit. Published at Monday, December 25th 2017, 03:27:19 AM. Voltage and current sources can be independent or dependent. Their respective circuit symbols. Independent sources are usually shown as a circle while dependent sources are usually shown as a diamond-shape. Independent sources can have a DC output or a functional output; some examples are a sine wave, square wave, impulse, and linear ramp. Dependent sources can be used to implement a voltage or current which is a function of some other voltage or current in the circuit. Dependent sources are often used to model active circuits that are used for signal amplification.
By Madeleine Catherine. Circuit. Published at Monday, December 25th 2017, 02:34:45 AM. Physical circuits are constructed of real, physical devices. They can be inspected, tested, and modified. They consume electric power when energized, and they can function properly and do some meaningful work, or they can malfunction and create serious hazards to health and property. Even small circuits that are quickly and easily constructed still take time and money to build, and they can take a very long time to perfect.
By Lydie Honorine. Circuit. Published at Monday, December 25th 2017, 02:27:56 AM. Many different types of components and devices can be found in modern circuits, including resistors, capacitors, and inductors, semiconductor devices like diodes, transistors, and integrated circuits, transducers like microphones, light sensors and motions sensors, actuators like motors and solenoids, and various other devices like heating and lighting elements. Devices in a circuit are connected to one another by means of electrical conductors, or wires. These wires can move electric currents between various points in a circuit. Once a wire connects two or more devices, the wire and all attached device connectors are said to form a single circuit node or net. Any electrical activity on a given net is communicated to all devices attached to the net. Certain nets provide electric power to devices, and other nets carry information between devices. Nets that carry information are called signals, and signals transport information encoded as voltage levels around a circuit. Signal nets typically use smaller conductors, and transport very small currents. Nets that carry power are called supply rails (or just supplies) and supply rails transport electric power around a circuit. Power nets typically use much larger conductors that signal nets, because they must transport larger currents.
By Alix Loane. Diode. Published at Monday, December 25th 2017, 02:07:04 AM. LEDs produce light of many colours in a very wide range of equipment from simple indicator lamps to huge and complex video displays. Photo diodes also produce electrical current from light.
By Lydie Honorine. Circuit. Published at Monday, December 25th 2017, 02:06:30 AM. Double-layer or double-sided PCBs have a base material with a thin layer of conductive metal, like copper, applied to both sides of the board. Holes drilled through the board allow circuits on one side of the board to connect to circuits on the other.
Altrushare - Wiring Diagram Gallery
Copyright © 2003 - 2018 Domain Media. All sponsored products, company names, brand names, trademarks and logos arethe property of their respective owners.