An LDO requires a minimum amount of headroom voltage to properly regulate V_OUT and still provide the desired load current, however this headroom voltage is not always available. By paralleling LDO's we can spread the load across multiple LDO's and thus we can operate with less headroom. If we assume that the data sheets dropout vs I_OUT curve is linear, we can approximate the maximum current an LDO can provide to the load without entering dropout. The maximum current an LDO can provide is either Equation 3 or the full rated current I_{LDO_MAX} listed in the data sheet.