blacksheep Posted May 18, 2006 Report Share Posted May 18, 2006 I don't know why it is so difficult to find datasheet with collector curves for any general purpose transistor. I have looked for datasheets for bc547, bc549, 2n2222 and others . Does anybody know where to find good datasheets with the Uce - Ic curves and Ube - Ib curves included for standard general purpose transistors? Quote Link to comment Share on other sites More sharing options...
audioguru Posted May 18, 2006 Report Share Posted May 18, 2006 Hi Blacksheep,You don't need collector curves for silicon transistors that are used well within their ratings. The current gain vs current is an absolute straight line!A curve of a typical base-emitter voltage is usually shown in datasheets, but doesn't mean much since each transistor with the same part number is different.I have Philips' 1968 databook which shows their metal-cased BC107 to BC109 in great detail. Collector curves with the lines separated by exactly the same distance, impedance curves and noise curves. The BC547 to BC549 are the same transistors in a modern plastic package.Transistors are cheap enough now to add plenty of negative feedback to make them more linear and the same.What are you making that requires a collector curve for its design? Quote Link to comment Share on other sites More sharing options...
blacksheep Posted May 19, 2006 Author Report Share Posted May 19, 2006 I am actually trying to understand how to design a transistor stage :) I don't know much about it and i think it is very confusing -- i don't know where to start and where to end. I thought about transferring the theory about vacuum tubes to transistor design, because i understand it better. In tube stage designing, the anode curves (collector curves for transistors) is used to get parameters such as amplification, internal resistance and others. I think it is a nice way to design and understand a tube circuit. Why is it so different with transistors? Is it the because of the difference between transistors of the same part number or is it just a totally different way of designing amplifier stages? I could really use a good book about small (audio) signal amplifiers using transistors... Quote Link to comment Share on other sites More sharing options...
audioguru Posted May 20, 2006 Report Share Posted May 20, 2006 A transistor operates completely differently than a vacuum tube. A common emitter stage has a voltage gain equal to the ratio of its collector resistor to its emitter resistor. If there is not an emitter resistor then the transistor will be sensitive to temperature, have very high distortion at high output levels and the voltage gain will have a max of about 100 due to the built-in resistance of its emitter.Look in our Articles section or in Google for good tutorials about transistors. Quote Link to comment Share on other sites More sharing options...
hotwaterwizard Posted May 21, 2006 Report Share Posted May 21, 2006 Here are the Curves for a 2N22222N2222_PN2222__MICRO.pdf Quote Link to comment Share on other sites More sharing options...
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