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Electronics => Electronics => Topic started by: Slothery on August 17, 2010, 09:07:35 AM

Title: Circuit Schematic Antics
Post by: Slothery on August 17, 2010, 09:07:35 AM

Alright so I am reading the book "Getting Started in Electronics" by Forrest M. Mims III and I still am confused with schematics. For example, in this circuit (first picture) why does Vout connect to the circuit before the photo-diode gets its reading? Finally, in the next picture the LEDs are hooked up before the resistors? How can this be if the resistors are needed to limit the current?

Title: Re: Circuit Schematic Antics
Post by: billhowl on August 17, 2010, 09:19:33 AM

Read this for LED connection
http://www.societyofrobots.com/robotforum/index.php?topic=11786.msg89175#msg89175 (http://www.societyofrobots.com/robotforum/index.php?topic=11786.msg89175#msg89175)
for photo-diode
http://www.societyofrobots.com/schematics_photoresistor.shtml (http://www.societyofrobots.com/schematics_photoresistor.shtml)

Title: Re: Circuit Schematic Antics
Post by: Slothery on August 17, 2010, 11:32:39 AM

I'm not concerned with the individual components more with the flow of electricity. Thanks though!

Title: Re: Circuit Schematic Antics
Post by: Razor Concepts on August 17, 2010, 04:45:39 PM

Electrons flow from negative to positive.

That doesnt matter anyways, the leds would work either way, before or after resistors. You cant look at a circuit component by component, you must look at the entire loop. Either way, the resistor limits the current, and the LED uses the rest.