blackshadow
New Member
i'm trying to develop a simple current regulator circuit using LM1084.
i intend to have a current limit of 3A.
R1 should be equal to 1.25V/3A = 0.413 ohms
ideally, per attached schematic, the voltage across R1 should be maintained with the internal Vref of 1.25V as we change the load current below 3A.
i simulated this on LT spice where it turned out that the Voltage across R1 is not maintained at 1.25V. instead Vref (Vout-Vload) increases from 0.2volt to 1.19V as we change load from 0.5A to 2.9A.
should'nt the Vref is kept at 1.25V? What's wrong?
i intend to have a current limit of 3A.
R1 should be equal to 1.25V/3A = 0.413 ohms
ideally, per attached schematic, the voltage across R1 should be maintained with the internal Vref of 1.25V as we change the load current below 3A.
i simulated this on LT spice where it turned out that the Voltage across R1 is not maintained at 1.25V. instead Vref (Vout-Vload) increases from 0.2volt to 1.19V as we change load from 0.5A to 2.9A.
should'nt the Vref is kept at 1.25V? What's wrong?
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