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ArcticMyst Security by Avery

Mp1584en

Joined
Feb 6, 2016
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48
Points
8
Can you use these as current regulator or do they only work as voltage regulators? The reason i ask is because i came across about 100 of them brand new. Thanks guys
 





Joined
Sep 12, 2007
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The feedback voltage is 0.8V, so yes. But it's pretty high to be ideal or efficient. You can add a current amplifier to the circuit to increase efficiency, but I'd recommend getting something with a lower feedback voltage in the first place.
 
Joined
Feb 6, 2016
Messages
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8
Alrighty so take me to school. I want to learn about voltage regulator being current regulators. Like I said these were free and I just took them home cause I am the type of guy that one day I will prolly use it so might as well keep it right? You talk about feedback voltage why does that affect it? Anything you can tell me would be great.
 
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If you're using a resistor to sense current (the simplest method), the higher the feedback voltage, the higher the power losses. This is because the voltage is used for sensing current instead of powering the load.
 
Joined
Feb 6, 2016
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Ok so i just got done looking through the datasheet again. Why does feedback voltage effect current reading. I get that higher voltages equal higher power losses but why is the feedback voltage 8 volts. And you said when using a resistor. What are other ways of sensing current with discrete components? I know you could always buy a current sensing ic but then that complicates things.
 

OVNI

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Oct 16, 2015
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There is an older post on making an MP1584 a constant current source here. The last post (#30) The Lightning Stalker declares success making a 1.4A constant current source using an MP1584 with modifications shown in schematic and pictures.
 
Last edited:
Joined
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Messages
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It's not 8V, it's 0.8V. And that was how the IC was designed - it is not something you can change. For sensing DC current with discrete components, a resistor is the only way that I know of.

I like I said, it would work, but would be less efficient than other designs.
 
Joined
Feb 6, 2016
Messages
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I meant .8 the . key fails on my laptop occasionally. And fair enough let me think of more questions
 




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