Doe anyone have a Sheet showing electronics equations? - Electronic Circuits Projects Diagrams Free

lompa · 8th April 2006, 02:20 PM

Hi im looking for a sheet of electronic equations like a PDF or something that i can print out and learn.

A level standard equations preferably, does anyone have one or know of a good link.

Thank you.

Russlk · 8th April 2006, 04:41 PM

You need to be more specific, there are lots of equations! Also, just knowing an equation does not mean you know how to apply it.

lompa · 8th April 2006, 05:19 PM

all the basic ones, resistance, charge, power, capacitance, transistor gain, inductance, impedance ect
Thanks

DigiTan · 8th April 2006, 05:23 PM

Although I convinced myself otherwise at the time, I tried learning through equations when I was in grade school and didn't learn jack. It's best to seek out a tutorial page like allaboutcircuits or something more comprehensive like a Shaum's Outline book.

DigiTan · 8th April 2006, 05:57 PM

Quote:

Originally Posted by lompa

all the basic ones, resistance, charge, power, capacitance, transistor gain, inductance, impedance ect
Thanks

Okay, that gives us something to go on.

* Resistance (R) is given by doing some manipulation of 0hm's Law. Since V= I*R, dividing both sides of the equation by "I" yeilds R = V/I.
--------------------
* Impedance (Z) is a combination of resistance (a real number) and reactance (an imaginary). Given that, you can expand 0hm's Law for more generality by saying: V= I*Z, or Z = V/I.
--------------------
* Because impedance is a complex number, there are actually several "types" of power (true, reactive, and appearant). In a DC circuit, we can stick to true power by saying: P = V*I -or- P = I²R -or- P = V²/R. All three are equivalent because of the V=I*R rule.
--------------------
* Charge (Q) is a measure of how many electrons occupy some finite space. Because charge is important while dealing with capacitors, we can say:
Capacitor Charge (Q) = Capacitor Voltage (V) * Capacitance (C)
--------------------
* Capacitance and Inductance are where Calculus comes into play. The capacitor voltage and current is always:
Vcapacitor = 1/C ∫ i(t) dt + Vinitial (integral limits: 0 to t)
Icapacitor = C * (di/dt)

The actual capacitance of a capacitor is set by the plate area, the plate spacing, and the dielectric material.
--------------------
* Inductors have a similar pattern:
Vinductor = 1/L ∫ v(t) dt + Iinitial (integral limits: 0 to t)
Iinductor = L * (dv/dt)

The actual inductance of an inductor is set by the number of turns, the radius of the coil, the core material, and the inductor length.
--------------------
* Transistor Current Gain is signified by β and α. (β is sometimes called "Hfe"). Beta is the ratio of collector current to base current. Alpha is the ratio of collector current to emitter current. So to sum it up: Beta = Ic/Ib. And Alpha = Ic/Ie. Also, the two are inter-related by:

α = β / (β + 1)
β = α / (1 - α) <--- Double-check me on this one

...it's important to note that β and α only describes the transistor and not the whole amplifier. Also, the two are not constant, and β tends to shrink and as the transistor saturates and begins carrying its maximum current.

lompa · 11th April 2006, 08:49 PM

Sorry for the delayed response. Thanks for the help it is much appreciated.

I knoow id can find the equations on google easily, i was looking for a ref sheet to keep for easy access.

zevon8 · 12th April 2006, 12:02 AM

If you go to a university or college book store, or even some regular book stores, there are what are called "crib sheets" or "cheat-sheets". They are laminated cards, 8 1/2 x 11 inch, ti fit in a 3 ring binder, they cover many topices, and are absolutely crammed front and back with data, including formulaes, charts, etc.

I don't remember who made the ones I have seen, but here is something similar:

http://www.videoed.com/c2627.html

stevez · 12th April 2006, 03:59 AM

I have several QUICK STUDY laminated cards- by Bar Charts Inc, Boca Raton, Florida, USA. Excellent with one "however" - useful as a quick reference if you understand the material. It might help as a supplement to other study materials or a good mentor but alone I think they'd create more problems than they solve. I suppose the important point is that if it helps you then it's the right tool.

Oznog · 12th April 2006, 06:42 AM

ELI the ICE man.
And something unsavory about resistor color codes.

ljcox · 14th April 2006, 02:41 AM

Some corrections in red below

Quote:

Originally Posted by DigiTan

Quote:

Originally Posted by lompa

all the basic ones, resistance, charge, power, capacitance, transistor gain, inductance, impedance ect
Thanks

Okay, that gives us something to go on.

* Resistance (R) is given by doing some manipulation of 0hm's Law. Since V= I*R, dividing both sides of the equation by "I" yeilds R = V/I.
--------------------
* Impedance (Z) is a combination of resistance (a real number) and reactance (an imaginary). Given that, you can expand 0hm's Law for more generality by saying: V= I*Z, or Z = V/I.
--------------------
* Because impedance is a complex number, there are actually several "types" of power (true, reactive, and appearant). In a DC circuit, we can stick to true power by saying: P = V*I -or- P = I²R -or- P = V²/R. All three are equivalent because of the V=I*R rule.
--------------------
* Charge (Q) is a measure of how many electrons occupy some finite space. Because charge is important while dealing with capacitors, we can say:
Capacitor Charge (Q) = Capacitor Voltage (V) * Capacitance (C)
--------------------
* Capacitance and Inductance are where Calculus comes into play. The capacitor voltage and current is always:
Vcapacitor = 1/C ∫ i(t) dt + Vinitial (integral limits: 0 to t)
Icapacitor = C * (di/dt) No, i = C dv/dt

The actual capacitance of a capacitor is set by the plate area, the plate spacing, and the dielectric material.
--------------------
* Inductors have a similar pattern:
Vinductor = 1/L ∫ v(t) dt + Iinitial (integral limits: 0 to t)
Iinductor = L * (dv/dt) No, v = L di/dt

The actual inductance of an inductor is set by the number of turns, the radius of the coil, the core material, and the inductor length.
--------------------
* Transistor Current Gain is signified by β and α. (β is sometimes called "Hfe"). Beta is the ratio of collector current to base current. Alpha is the ratio of collector current to emitter current. So to sum it up: Beta = Ic/Ib. And Alpha = Ic/Ie. Also, the two are inter-related by:

α = β / (β + 1)
β = α / (1 - α) <--- Double-check me on this one

...it's important to note that β and α only describes the transistor and not the whole amplifier. Also, the two are not constant, and β tends to shrink and as the transistor saturates and begins carrying its maximum current.

DigiTan · 14th April 2006, 04:54 AM

di/dt and dv/dt. Sometime I have trouble...differentiating between the two. :lol:

ljcox · 14th April 2006, 10:45 AM

Quote:

Originally Posted by DigiTan

di/dt and dv/dt. Sometime I have trouble...differentiating between the two. :lol:

Yes, we all have that problem occasionally. I also appreciated the joke.

neon · 14th April 2006, 12:41 PM

LOOK WHAT YOU NEED IS A REFERENCE DATA BOOK mine is for radio a nd electronics for engineers and it is old by INTERNETIONAL TELEPHONE AND TELEGRAPH CORPORATION. It has anything you want in there from the size of wire to screw size to KLYSTRON ,LAPLACE TRANSFORM you name it. mine is forth edition pay the money and it will stay with you forever. do you know the sign of a good engineer is a GUY THAT KNOW WHAT BOOK TO GO TO FIND THE ANSWERS. And another book if SYSTEN ANALISYS by philip & cutler.you learn these 2 books you got it.

DevStack · 8th May 2007, 02:33 PM

I have a cheat sheet I downloaded from another site in .pdf
Devilbabytales@aol.com
Mention Electronics Cheat Sheet

TheVictim · 8th May 2007, 03:05 PM

The gain (Hfe) of transistors listed on their datasheet is an approximation. Some transistors can have up to 200% of this value, even "complimentary pairs" for use in push-pull amplifiers (where the gain needs to be a pretty close match). Don't trust the datasheets. Adjust the values of your emitter and/or collector resistors for the appropriate gain, and don't bypass the emitter resistor with a cap for extra AC gain, because you won't know for sure what that gain will be.

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8th April 2006, 02:20 PM	(permalink)
lompa	Doe anyone have a Sheet showing electronics equations? Hi im looking for a sheet of electronic equations like a PDF or something that i can print out and learn. A level standard equations preferably, does anyone have one or know of a good link. Thank you.

8th April 2006, 04:41 PM	(permalink)
Russlk	You need to be more specific, there are lots of equations! Also, just knowing an equation does not mean you know how to apply it. __________________ see my website: www.geocities.com/russlk

8th April 2006, 05:19 PM	(permalink)
lompa	all the basic ones, resistance, charge, power, capacitance, transistor gain, inductance, impedance ect Thanks

8th April 2006, 05:23 PM	(permalink)
DigiTan	Although I convinced myself otherwise at the time, I tried learning through equations when I was in grade school and didn't learn jack. It's best to seek out a tutorial page like allaboutcircuits or something more comprehensive like a Shaum's Outline book. __________________ The most-hated young engineer in America. * AVR Projects * Robot War: TI * About

11th April 2006, 08:49 PM	(permalink)
lompa	Sorry for the delayed response. Thanks for the help it is much appreciated. I knoow id can find the equations on google easily, i was looking for a ref sheet to keep for easy access.

12th April 2006, 12:02 AM	(permalink)
zevon8	If you go to a university or college book store, or even some regular book stores, there are what are called "crib sheets" or "cheat-sheets". They are laminated cards, 8 1/2 x 11 inch, ti fit in a 3 ring binder, they cover many topices, and are absolutely crammed front and back with data, including formulaes, charts, etc. I don't remember who made the ones I have seen, but here is something similar: http://www.videoed.com/c2627.html

12th April 2006, 03:59 AM	(permalink)
stevez	I have several QUICK STUDY laminated cards- by Bar Charts Inc, Boca Raton, Florida, USA. Excellent with one "however" - useful as a quick reference if you understand the material. It might help as a supplement to other study materials or a good mentor but alone I think they'd create more problems than they solve. I suppose the important point is that if it helps you then it's the right tool. __________________ stevez

12th April 2006, 06:42 AM	(permalink)
Oznog	ELI the ICE man. And something unsavory about resistor color codes. __________________ I thought what I'd do was I'd pretend I was one of those deaf-mutes.

14th April 2006, 04:54 AM	(permalink)
DigiTan	di/dt and dv/dt. Sometime I have trouble...differentiating between the two. :lol: __________________ The most-hated young engineer in America. * AVR Projects * Robot War: TI * About

14th April 2006, 12:41 PM	(permalink)
neon	LOOK WHAT YOU NEED IS A REFERENCE DATA BOOK mine is for radio a nd electronics for engineers and it is old by INTERNETIONAL TELEPHONE AND TELEGRAPH CORPORATION. It has anything you want in there from the size of wire to screw size to KLYSTRON ,LAPLACE TRANSFORM you name it. mine is forth edition pay the money and it will stay with you forever. do you know the sign of a good engineer is a GUY THAT KNOW WHAT BOOK TO GO TO FIND THE ANSWERS. And another book if SYSTEN ANALISYS by philip & cutler.you learn these 2 books you got it.

8th May 2007, 02:33 PM	(permalink)
DevStack	I have a cheat sheet I downloaded from another site in .pdf Devilbabytales@aol.com Mention Electronics Cheat Sheet

8th May 2007, 03:05 PM	(permalink)
TheVictim	The gain (Hfe) of transistors listed on their datasheet is an approximation. Some transistors can have up to 200% of this value, even "complimentary pairs" for use in push-pull amplifiers (where the gain needs to be a pretty close match). Don't trust the datasheets. Adjust the values of your emitter and/or collector resistors for the appropriate gain, and don't bypass the emitter resistor with a cap for extra AC gain, because you won't know for sure what that gain will be.