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glossary:glossary_i [2013/04/07 08:41]
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glossary:glossary_i [2020/05/08 06:13] (current)
tgerbic [ICs]
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 ===== ICs ===== ===== ICs =====
  
 +An integrated circuit (IC) is an electronic component which typically packages a collection of transistors, diodes and resistors to perform some useful function. There are numerous types with many package configurations. You may be familiar with fairly simple ones like Operation Amplifiers (Op Amps) or "555" timers, or complex types like microprocessors. Modern ICs are generally encased in a square/rectangular plastic package with many leads/pins. Pins are commonly spaced on a 0.1"(2.54mm) grid which will fit the holes on stripboard and breadboards. This packaging is usually referred to as Through Hole mounting as the pins normally go through holes in a PCB. Newer ICs can be found with much closer pin spacing and very small packages, usually designed for surface mounting on PCBs.
  
-Integrated Circuits are usually called ICs or chips. They are complex circuits which have been etched onto tiny chips of semiconductor (silicon). The chip is packaged in a plastic holder with pins spaced on a 0.1"(2.54mm) grid which will fit the holes on stripboard and breadboards. Very fine wires inside the package link the chip to the pins.\\ 
-{{:glossary:ic.gif}}\\ 
-[[http://www.kpsec.freeuk.com/components/ic.htm|http://www.kpsec.freeuk.com/components/ic.htm]] 
  
 +===== ICSP =====
 +
 +In Circuit Serial Programming is a means whereby microprocessors (PICs and other types), may be programmed while mounted in the circuit they are intended to control. There are no standard physical designs/pinouts used for in-circuit programming. Many MERG modules using PIC microprocessors are provided with an ICSP connector with a pinout for the popular PICKIT programmer.\\
 +[[:helpsystem:pickit2cbus|Pinout shown here.]]\\
  
 ===== Incandescent lamps ===== ===== Incandescent lamps =====
  
  
-Lamps emit light when an electric current passes through them. All of the lamps shown on this page have a thin wire filament which becomes very hot and glows brightly when a current passes through itThe filament is made from a metal with a high melting point such as tungsten and it is usually wound into a small coil. \\ +Incandescent lamps emit light when an electric current passes through a thin wire filamentwhich becomes very hot and glow brightly. Filament lamps may have a shorter lifetime than most electronic components because the filament could melt at a weak point. Incandescent lamps, such as the tiny "grain-of-rice or grain-of-wheat" lamps shown in the second image, have been used for decades as model engine lights, signaling lights and for layout structure lighting. There is a movement to replace incandescent lamps with light emitting diodes (LEDs) which use less power, generate less heat and typically last longer.  
-Filament lamps have a shorter lifetime than most electronic components because eventually the filament 'blows' (melts) at a weak point. + 
- \\ {{:glossary:lamp-1.jpg}}{{:glossary:lamp-2.jpg}}+ \\ {{:glossary:lamp-1.jpg}}\\ 
 + 
 +{{:glossary:lamp-2.jpg}}\\ 
  \\ [[http://www.kpsec.freeuk.com/components/lamp.htm|http://www.kpsec.freeuk.com/components/lamp.htm]]  \\ [[http://www.kpsec.freeuk.com/components/lamp.htm|http://www.kpsec.freeuk.com/components/lamp.htm]]
  
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 ===== Inductor ===== ===== Inductor =====
  
-An inductor is a coil of wire which may have a core of air, iron or ferrite (a brittle material made from(iron). Its electrical property is called inductance and the unit for this is the henry, symbol H. 1H is very large so mH and uH are used, 1000uH and 1000mH=1H. Iron and ferrite cores increase the induction. \\ +An inductor is a coil of wire which may have a core of air, iron or ferrite (a brittle material made from iron). Its electrical property is called inductance and the unit for this is the Henry, symbol H. 1H is very large so mH and uH are used, 1000uH=1mH and 1000mH=1H. Iron and ferrite cores increase the inductance. \\ 
-Inductors are mainly used to tune circuits and to block high frequency AC signals (they re sometimes called chokes) \\ +Inductors are mainly used to tune circuits and to block high-frequency AC signals (they're sometimes called chokes) \\ 
-They pass DC easily, but block AC signals ,This is the opposite to capacitor.+They pass DC easily, but block AC signals; this is the opposite action to capacitor.
  \\ {{:glossary:inductor.jpg}}  \\ {{:glossary:inductor.jpg}}
  \\ [[http://www.kpsec.freeuk.com/components/other.htm#inductor|http://www.kpsec.freeuk.com/components/other.htm#inductor]]  \\ [[http://www.kpsec.freeuk.com/components/other.htm#inductor|http://www.kpsec.freeuk.com/components/other.htm#inductor]]
  
  
-===== Infra red emitter ===== +===== Infrared emitter =====
  
-These IR emitters are high intensity Gallium Arsenide infrared emitting diodes mounted in clear plastic with smoke color lens. They are made with Gallium Aluminum Arsenide window layer on Gallium Arsenide Infrared emitting diodes. Viewing angle is 20 degrees+These are light emitting diodes (LEDs) which emit light outside of the visible light spectrum. 
 +IR emitters are generally mounted in plastic with clear or smoke color lens.
  \\ {{:glossary:ir-emit.jpg}}  \\ {{:glossary:ir-emit.jpg}}
  
-===== Infra red receiver/detector =====+===== Infrared receiver/detector =====
  
-Two types of IR receivers are used, a phototransistor or a photodiode+There are two common types of IR detectors, a phototransistor or a photodiode. These detectors are fabricated to detect light in the IR spectrum. 
  \\ {{:glossary:ir-rec.jpg}}  \\ {{:glossary:ir-rec.jpg}}
  
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-Name for means of linking the operation of points and signals such that signals can only show a proceed aspect when points are correctly set, and that points cannot be moved unless the signals over them are showing stop aspects. Interlocking can be mechanical, electrical using relays or carried out by computers.+Name for means of linking the operation of points and signals such that signals can only show a proceed aspect when points are correctly set, and that points cannot be moved unless the signals over them are showing stop aspects. Interlocking can be mechanical, electrical using relays or carried out by computers.
  
 +=====ISR=====
  
 +An Interrupt Service Routine is a firmware/software program subroutine (sub-program) triggered by a microprocessor hardware pin. When triggered, the processor will temporarily execute a subroutine then return to the previous program execution. An ISR can be used to make the processor immediately take care of a time critical operation. While there are many uses for an ISR, some common uses would be for receiving serial bits from a serial data interface or sensing an external clock signal to trigger the sending of video signals at a precise time. In some cases there are more than one interrupt trigger pin or indication. Because of this there may be priority settings. A High priority interrupt cannot itself be interrupted whereas a Low priority interrupt can be interrupted by a High level one. This helps keep multiple ISRs from interfering with each other. 
glossary/glossary_i.1365324104.txt.gz · Last modified: 2014/11/11 13:27 (external edit)