# Active and resistive load current

Discussion in 'General Electronics Discussion' started by kalpana, Jun 17, 2016.

1. ### kalpana

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Jun 17, 2016
Can anyone tell me what is active load current and static resistive load current and what is the difference between both?

2. ### Sunnysky

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Jul 15, 2016
one can use a transistor for an amplified current controlled load or voltage controlled load with current sense.

it is useful to have a ramp controlled active load for testing dc power or step load for stability.

static in this is not Q charges but means opposite of dynamic or active.

3. ### Ratch

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Mar 10, 2013
Current in a circuit measures the same no matter what causes it. I have never heard of those two terms you are asking about. Can you provide a link to some easy to access document where those terms are mentioned?

Ratach

4. ### Sunnysky

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Jul 15, 2016
"Active load" means using any semiconductor. You can easily find commerical active loads or simple circuits for special,purposes.

Passive does not.

5. ### Ratch

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Mar 10, 2013
So, how are their currents different?

Ratch

6. ### Sunnysky

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Jul 15, 2016
same noun.
dont be silly.

7. ### Ratch

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Mar 10, 2013
The OP asked what is the difference between active load current and static resistive load current. Before that can be answered, those terms have to be defined. To just say that those "adjectives" are not the same is a distinction without a difference. So, it is not "silly" to wonder what the OP means by those terms.

Ratch

8. ### Sunnysky

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Jul 15, 2016

Active and passives can deliver the same current if they have the same resitance.

A fixed resistor is passive and Ohm's and Kirchoff's Laws apply.

An active semiconductor controlled current will have some defined transfer function with some parametric control such; as constant current, voltage or some non-linear function.

9. ### Ratch

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Mar 10, 2013
Yes, that is the topological circuit difference, but the OP asked what is the difference in current. Can an ammeter tell the difference? Inquiring minds would like to know.

Ratch

10. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Jan 21, 2010
I'm with Ratch. I have no idea what those terms mean.

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Jul 15, 2016

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Jul 7, 2015

13. ### Sunnysky

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Jul 15, 2016
it seems pointless to describe current unless you define the load and voltage.

Now the same current can be duplicated either way if one matched the active load resistance for linear operation if one needs reassurance of that.

But more likely, active non-linear loads are useful not as fixed Resistors but for adjustable loads , for reasons beyond the scope of this question. such as CC loads for reducing supply or temp. sensitivity.

Another example is if you smoothen current with sufficient capacitance, you can switch a fixed low value of R to be any value higher using PWM or duty cycle control.

14. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Jan 21, 2010
How can it be pointless?

I know what an active load is, and I know what a resistive load is, and I know what current is.

However, unless someone defines the properties of the active load, I can say less about it than I can for the resistive load.

If the question were about a reactive load current and a resistive load current then there would be a prospect of them having differentiation due to their phase relationship with the load voltage.

Perhaps all I could say is that resistive load current will always be proportional to the load voltage, a relationship which may not exist for an active load.

15. ### Sunnysky

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Jul 15, 2016
I agree, it is pointless for further discussion.

hevans1944 likes this.
16. ### hevans1944Hop - AC8NS

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Jun 21, 2012
The original poster, @kalpana, joined EP on June 17, 2016, and posted his question that same day. Since then, there has been no response from the OP. Nada. Nothing. Meantime, regular posters here have been playing "ring around the rosie" with the question. It's more than past time to stop playing the game and go on to more interesting questions.

My two cents: if you want to think there is some sort of distinction between "active load current and static resistive load current" feel free to look elsewhere for answers.