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Varialbe current regulator? Answered

Have you ever seen a variable current regulator? i googled it but i keep getting standard voltage regulators Any help would be appreciated!

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Padlock

10 years ago

Correct me if I'm wrong, but wouldn't this be called a potentiometer?

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Sandisk1duoPadlock

Reply 10 years ago

yes, that would work, BUT for low amperage/voltage, i need something heavy duty

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Sandisk1duoSandisk1duo

Reply 10 years ago

ya, in theory all this is a digital potentiometer, but i need it to control amperage, and amperage only

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Sandisk1duoPadlock

Reply 10 years ago

as heavy duty as it's available, like 30W

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Goodhart

10 years ago

would a "current controlled resistor" work ? Or maybe a thyristor (SCR)?

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GoodhartSandisk1duo

Reply 10 years ago

The first picture is a voltage controlled resistor, the second of an SCR (the third pic is the schematic for the PNP device) the last pic is an SCR being used.

Figure_01.gifSell_X0405_SCR.jpgthyristor_equiv_circuit.gifscr_overvoltage_crowbar.gif
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Sandisk1duoGoodhart

Reply 10 years ago

what is Vg1 and Vg2? i don't know what device that is? looks like a mofset?

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GoodhartSandisk1duo

Reply 10 years ago

Vg, in this case most likely refers to VoltagegateIn (not power supply) typical symbols are pictured below.

FIG1.GIF
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GoodhartSandisk1duo

Reply 10 years ago

I haven't fooled around with voltage controlled resistors before; I just happened to have heard of them. Which is why I also wondered if an SCR (silicon control rectifier) might not work better.

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Padlock

10 years ago

Theres a one at radioshack for 2.29 ... Not really cheap but if you only need one.

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Sandisk1duoPadlock

Reply 10 years ago

ya, probably a regular voltage regulator that only regulates voltage, not amperage (it only limits it to 1.5Amps)

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PadlockSandisk1duo

Reply 10 years ago

Oh, I'm sorry, I didn't see the current part. I thought it was voltage.

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westfw

10 years ago

Yeah, check out the datasheets for LM317 or LM117. These can be made to output a specific current as well as a specific voltage, and most of the datasheets will include a CCCV "lab-style" power supply circuit.