Dynamically controllable current reference technique for current-feedback low dropout regulator

This paper proposes the dynamically controllable current reference (DCCR) technique for a wide input range, transient enhancement current-feedback low dropout regulator (WTELDO) to achieve transient enhancement. Combined with a transient enhanced current mirror (TE-CM) adopting an enhanced active resistance network, this technique which is designed based on dynamic bias improves the slewing rate of the power transistor gate but also increases the loop bandwidth. Finally, this WTELDO can reduce the minimum input voltage due to the current-feedback technique and improve the transient response under the condition of maintaining low quiescent current. This designed WTELDO was fabricated in SMIC 0.18μm CMOS process. The input voltage range is 0.8–2.2 V. The output voltage is 0.64 V. The maximum load current is 50 mA and the static current consumption is about 26 μA. Its maximum current efficiency is up to 99.948%. The test results show that the overshoot is 117.5 mV and the undershoot is 167.5 mV when the load current is switched between 0 mA and 50 mA within 300 ns under a 100 pF load capacitor.