Cross-Regulation-Suppression control scheme for CCM Single-Inductor-Dual-Output buck converter with ordered-power-distributive control

Abstract

A Single-Inductor-Dual-Output (SIDO) buck converter with Cross-Regulation-Suppression (CRS) control scheme is presented. The converter operates in continuousconduction-mode (CCM) and employs ordered-powerdistributive control (OPDC) to distribute the inductor current to the two outputs. The novel CRS control method is used to suppress the cross-regulation (CR) of the SIDO which is an important issue in OPDC CCM converter design. On-chip type-III compensator is incorporated in the SIDO converter to eliminate off-chip components and accelerate system response. The CRS controlled converter is fabricated with AMS 0.35µm CMOS process and operates at 2MHz. Measurement results show that this converter achieves a cross-regulation down to 0.056mV/mA with 180mA load current changes and a response time less than 20µs. The maximum efficiency is 91.8%.

Voltage‐mode hysteretic control techniques for high‐current single‐inductor multiple‐output switching regulators

“…For traditional PWM controlled SIMO converters [1][2][3], the dutycycle to turn on and off the high-side and low-side power transistors (shown as M H and M L , respectively, in Fig. 1) to charge and discharge the inductor, as well as the output steering switches that select paths to distribute the inductor current to different outputs (illustrated as M 1 and M 2 , respectively, in Fig.…”

“…The cross-regulation will be more significant at heavy load conditions because the controllers were designed to handle crossregulations only up to a certain current level, and the interruption in control timing and current delivery will result in larger voltage fluctuations. As a result, the maximum output current capacity per output for SIMO converters is limited typically well below 1 A [1][2][3][4][5][6][7][8].…”

Low power AC-DC converters for wireless power transfer application

“…To mitigate the problem, time-multiplexing control and ordered power distributive control are employed to minimize the error of the energy transfer. However, both of the controls are still susceptible to cross regulation problem when one of the loads draw more energy than the others [61][62], [58,64]. The multiple-output LDO (MOLDO) is proposed in [167] to cater for multiple LDO outputs.…”

“…Cross regulation means that any load change at one output will cause the instability of voltage at another output due to insufficient or excess charge [56][57][58][59][60], which is shown in Fig. 2.31.…”

“…For a dual-output converter, both of the output voltages share the same energy in the inductor [58], [64]. The inductor is only charged once and the energy is But this method is vulnerable to the cross regulation problem as well.…”