Low dropout linear regulator with no off-chip capacitor and low power consumption
Lenian He · Journal of Zhejiang University(Engineering Science) · 2009
A low dropout linear regulator(LDO) with no off-chip capacitor and maximal output current of 100 mA and 3.3 V output voltage was designed and implemented by using CSMC's 0.5 μm mixed-signal technology.By using a parallel structure constituted by differentiator,Miller capacitor and error amplifier,the circuit can supply a large current for state conversion in a moment.Therefore,when the load current or supply voltage changes,the varieties of transient output voltage are acceptable under the condition of no off-chip capacitor.The chip testing results revealed that under the supply voltage of 5 V,as the load current decreased from 100 mA to 1 mA within 1 μs,the ripple of output voltage was less than 600 mV;and the quiescent current was measured to be less than 4.5 μA.The designed circuit was validated by the results of the chip test.