Transistor Design

10 comments

Anonymous Poster	Transistor Design 09/21/2006 1:03 PM
	Design and implement a transistor switching circuit to switch two LEDs in series, on and off. The design should use one npn BJT, a DC power supply, a signal generator and some resistors. The input to the circuit is a square wave oscillating between 0 and 3 volts. The frequency of the wave should be such that the LED stays on for 1 sec and goes off for 1 sec. The current through the two LED's should be 10mA, while the DC power supply should be 10V.
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steve-o Power-User Join Date: Jun 2006 Location: Southwest Virginia, United States Posts: 365	#1 Re: transistors 09/21/2006 2:31 PM
	What is the application?
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jack of all trades Guru Join Date: Sep 2006 Location: Auckland, New Zealand Posts: 8777 Good Answers: 376	#2 Re: Transistor Design 09/21/2006 8:29 PM
	There, done. Do I get a prize for being first? . No, well please feel free to not inform us all of the answer when you get your homework assignment back (assuming you get the right answer). Some of us are still working on the problem. __________________ jack of all trades
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Bill Guru Join Date: Dec 2005 Location: Clemson, South Carolina Posts: 1722 Good Answers: 18	#3 Re: Transistor Design 09/22/2006 7:23 AM
	It's early in the semester; problems assigned are very easy; things will get much tougher than the LED flasher; you're in trouble. Might want to think about dropping the course . . . __________________ We have met the enemy and he is us . . . Walt Kelly
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jowens Power-User Join Date: Nov 2005 Location: Princess Anne, Maryland USA Posts: 184	#4 Re: Transistor Design 09/22/2006 7:58 AM
	If I do this for you I need you to design a wireless monitoring system for all the AC motors in my plant. I would also like "Real Time" individual current draws and and motor operating Temps. so I can forcast failures. __________________ “The problems we face cannot be solved with the same level of thinking we had when they were created” Albert Einstein
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Anonymous Poster	#5 Re: Transistor Design 09/22/2006 10:33 AM
	Well, it would assume that the duty cycle of the incoming signal is... What? 0.5 hertz or so... So that you do get a "On one second" and "Off one second." Not too hard. By the way... I have been out of 'the loop' for some 10 to 15 years... What is a npn BJT? The closest thing I can think of is a Bi-polar JFET because of the npn notation.
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steve-o Power-User Join Date: Jun 2006 Location: Southwest Virginia, United States Posts: 365	#6 In reply to #5 Re: Transistor Design 09/22/2006 10:53 AM
	bipolar junction transistor. bjt. standard npn like 2n2222 or such, I believe
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Anonymous Poster	#7 In reply to #6 Re: Transistor Design 09/22/2006 11:05 AM
	Ahh! Ok.
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Shyam Guru Join Date: Aug 2006 Location: AM-51, Deen Dayal Nagar, Gwalior, Madhya Pradesh, MP 474001, India Posts: 3418 Good Answers: 32	#8 Re: Transistor Design 09/25/2006 1:27 AM
	Use a common emitter circuit with 1k resistance to base and connected to trigger signal. Emitter to Ground and collector with 100 ohms in series with two LEDs to collector of transistor BC548, sourced by the power voltage 5V range. __________________ Prof. (Dr.) Shyam, Managing Director for Sensors Technology Private Limited. Gwalior, MP474001, India.
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maveric_manic Guru Join Date: Apr 2009 Location: Los Angeles, California USA Posts: 553 Good Answers: 1	#9 Re: Transistor Design 10/27/2009 10:44 PM
	You need to ask a question we are not going to design a circuit for you. __________________ Regards, Maveric Manic - 'Knowledge is Power and Wisdom is knowing how to use it'
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Anonymous Poster (3); Bill (1); jack of all trades (1); jowens (1); maveric_manic (1); Shyam (1); steve-o (2)

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