A fast-transient on-chip LDO with advanced dynamic biasing circuit

This paper presents a low dropout regulator (LDO) with a low quiescent current which helps to extend the standby time of battery-powered electronic devices. By utilizing the switchable bias technique in the error amplifier (EA), the bias current is switched to a higher level to accelerate the transient response under heavy load, while a low bias current is applied to EA to maintain a low quiescent current under light load. High speed current comparators and hysteresis control are combined to ensure fast and stable switching operation of the bias current. Moreover, an inrush current suppression circuit is proposed by recycling the switchable bias in EA. During startup, the bias current of EA can be kept low, and a reduced slew rate can be obtained at the pass gate voltage. The proposed LDO has been fabricated in 0.18-μm CMOS process, The experimental total quiescent current is 300nA under no-load condition. The maximum load current is 300mA. Measurement results show that the LDO can be settled within 8μs for a load current step of 0-50mA. In the startup process, the measured inrush current can be effectively limited.

Section: Introductionmentioning

confidence: 99%

Design of 300nA quiescent current and 300mA load capacity LDO with fast transient response

Yu,

Gao,

Zhang

et al. 2024

“…Compared to traditional PI control, MPC can be used to handle multiple variables and constraints and adapt to the nonlinear and time-varying nature of the system [27]. This can improve the dynamic response and steady-state accuracy of the system, and reduce the steady-state error of the system [28].…”

Section: Introductionmentioning

confidence: 99%

Model predictive control strategy based on Kalman filter for dual active bridge converter

Yan,

Hua,

Xun

et al. 2024

With the widespread use of electric vehicles, the large disturbance caused by the uncertainty of the AC side of the power grid will adversely affect the voltage stability of the DC side of the charging pile, which will threaten the charging safety of electric vehicles. In order to achieve fast and adaptive DC voltage regulation under large disturbance, this paper proposes a dual active bridge (DAB) converter control strategy based on Kalman Filter (KF) and Model Predictive Control (MPC). The improved Euler method is used to obtain a more accurate DAB discrete model, and the MPC control system is designed to improve the control accuracy. The best observation results of KF are used as feedforward compensation to improve the accuracy of output voltage regulation and ensure the stability of electric vehicles in the face of various disturbance problems. Finally, the effectiveness of the control strategy is verified by experiment.

“…The efficiency of DC-DC converters can reach more than 90% [1,2,3,4,5,6,7,8,9]. However, its large output ripple limits its applications in sensitive electronic load where additional LDO is required to achieve low power noise and ripple [10,11,12,13,14,15,16,17,18,19]. Hybrid methods of switched-mode, switched-capacitor-mode DC-DC, low dropout voltage regulator (LDO) are proposed in recent years [20,21,22,23,24].…”

Section: Introductionmentioning

confidence: 99%

A novel DC-DC converter and LDO cascaded circuit with improved dynamic response and loop stability

Zhou

Min

Luo

2021

Presented is a new type of DC-DC converter and low dropout voltage regulator (LDO) cascaded circuit, which has improved dynamic response and loop stability. In this novel cascaded circuit, the gate voltage of the pass element of the LDO is quantized and compared with a target value to form an error value to finally control the feedback coefficient of the DC-DC converter. Meanwhile, the adjusting speed of this feedback coefficient can be changed dynamically through the gain compensator, which is minimized to obtain the best loop stability when approaching the steady-state and increased to achieve a fast transient response during large dynamic change. The testing results of the prototype designed to verify the feasibility show that the novel cascaded circuit can increase the response speed by 22 times and optimize the voltage ripple by 1.9 times.