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A possible stability problem that occu rs in monolithiclinear regulators is current limit oscillations. The LT1585/LT1587 essentially have a flat current limit over the range of input supply voltage. The lower current limit rating and 7V maximum supply voltage rating for these devices permit this characteristic. Current limit oscillations are typically nonexistent, unless the input and output decoupling ca- pacitors for the regulators are mounted several inches from the terminals. The LT1584 differs from the LT1585/ LT1587 and provides current limit foldback as input-to- output difterential voltage increases. This safe-area char- acteristic exhibits a negative impedance because increas- ing voltage causes output current to decrease. Negative resistance du ring current limit is not unique to the LT1584 devices and is present on many power IC regulators. The value of the negative resistance is afunction of how fast the current limit is folded back as input-to-output voltage increases. This negative resistance can react with capaci- tors and inductors on the input and output to cause oscillation du ring current limit. Depending on the values of series resistances,the overall system may end up unstable. However, the oscillation causes no problem and the lC remains protected.ln general, if this problem occurs and is unacceptable,increasing the amountofoutput capacitance helps dampen the system.