where to connect resistor on LT3015 parallel operation? (neg ldo)

[coppercone2]

The datasheet for the LT3015 has a circuit for parallel operating chips involving a op-amp.

It uses 0.01 ohm resistors for each op - amp, and a sense on the line between the resistor and the op amp.

Should the trace be connected at the 0.01 ohm resistor, or at the input to the chip?



i put red and green dots

[moffy]

Should the trace be connected at the 0.01 ohm resistor, or at the input to the chip?

At the 0.01R resistors, that is what you are measuring the voltage drop over, extra trace will just add extra resistance.

[PCB.Wiz]

As drawn looks correct.
The top regulator defines VOUT, and the Opamp compares the current draw, and nudges the setting of the lower regulator, to give equal average currents.
Such a circuit may need care at very low load currents.

[coppercone2]

yeah that is what I did, I put the trace right at the end of the resistor (I used a wire shunt from digikey).

The regulators are hard to space evenly because I wanted a single extruded heat sink so the traces are unequal.