The technique discussed above compensates for the amplifier’s offset voltage and yields an accurate regulator, but only at a specific temperature. In most amplifiers, the offset voltage change with temperature is proportional to the initial offset level. Trimming the output voltage sampling element, does not reduce the offset voltage but merely counteracts it. At a different ambient temperature, the offset voltage changes and, thus, error is again introduced into the voltage regulator.
Monolithic integrated circuit regulators use technology that essentially eliminates offset in integrated circuit amplifiers. With minimal offset voltage, drift caused by temperature variations will have little consequence.