http://circuitcalculator.com/wordpress a blog with live web calculators... Thu, 17 Jul 2008 23:01:38 +0000 http://backend.userland.com/rss092 en From time to time, I get questions about antennas (particularly PCB antennas), so I figured I would at least make a small "stub" of a post to serve as a place to discuss the topic. For example, Sia writes "How can we find the impedance?" For antenna impedance (and other antenna properties), ... http://circuitcalculator.com/wordpress/2008/04/25/pcb-antennas/ Sitting actually puts a lot strain on your lower back. Over the years, working at a desk job can really injure your back so that you won't be able to sit comfortably for extended periods of time anymore. After suffering such an injury myself, I found that the only way ... http://circuitcalculator.com/wordpress/2008/03/14/save-your-back-by-using-a-high-desk/ Question: I would like to know how a circuit designer in OrCAD plans the schematic and layout for the digital, analog, power, low speed high speed portion of the PCBs? Answer: Wow, this is a big but good question! For anyone considering undertaking a schematic capture and PCB layout for the first ... http://circuitcalculator.com/wordpress/2008/03/07/schematic-and-pcb-design-process/ Here is a Zoho Sheet to do various 3-Phase calculations. It can convert between line-to-line and line-to-neutral voltages, find current based on apparent power (KVA), and choose the required wire cross sectional area to meet the target voltage drop. When designing such a system, you must also meet all applicable ... http://circuitcalculator.com/wordpress/2008/01/05/3-phase-calculations/ This Javascript web calculator will calculate the resistance and ampacity for copper wire based on the gauge. Both metric (mm) and American Wire Gauge (AWG) are supported. Note: Ampacity is based on a curve fit to MIL-STD-975. To see the wire table that this calculator is based on as well ... http://circuitcalculator.com/wordpress/2007/09/20/wire-parameter-calculator/ This web calculator converts numbers between the hexadecimal (hex), decimal, and binary formats. The calculator was designed to allow easy conversion between any of these three formats. This task is very common for those working with digital hardware and software including microcontrollers, DSP's, FPGA, etc. Tips: Type a number into any ... http://circuitcalculator.com/wordpress/2007/06/29/hex-decimal-and-binary-converter/ Electrical current always flows in the path that results in the lowest expenditure of energy. At lower frequencies, current flows in a path that reduces I^2*R losses. This is the path of shortest distance and is fairly intuitive to think about. At higher frequencies, things get a little strange. Current takes ... http://circuitcalculator.com/wordpress/2007/06/18/skin-effect-calculator/ When minimum cost and high-speed are required, a four-layer board may be the answer. High-Speed PCB design generally requires controlled impedance traces and good power and ground planes in order to meet signal integrity and power integrity requirements. Four-Layer PCBs are essentially made of 2 two-layer hardboards "glued" together with ... http://circuitcalculator.com/wordpress/2007/05/29/four-layer-high-speed-pcb-design/ Review: A new PCB stack-up design and impedance calculator is available for download from Istvan Nagy (see link below). It is a full-featured Excel-based tool that helps plan the PCB stack-up so that controlled impedance traces can be effectively implemented. It covers both single-ended and differential traces and is based ... http://circuitcalculator.com/wordpress/2007/05/12/pcb-stack-up-design-and-impedance-calculator/ A novel SPICE simulation technique was developed to investigate the effects of corners in PCB traces. The PCB traces were modeled by breaking them down into tiny squares or finite elements. A SPICE sub-circuit was made for the finite element and a small square symbol with one pin on each ... http://circuitcalculator.com/wordpress/2007/04/06/effects-of-corners-in-pcb-traces/