Linear-assisted DC/DC converters with modified current-mode control applied to photovoltaic solar systems

This article shows the proposal of a current-mode one-cycle control for linear-assisted DC/DC converters. Linearassisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators (classic NPN topology or LDO –low dropout–) and switching DC/DC converters. The current-mode one-cycle control technique is proposed in order to obtain the duty cycle of the linear-assisted converter switch. The proposed structure can provide an output with suitable load and line regulations. Thus, the paper shows the design and simulation results of the proposed current-mode one-cycle linear-assisted converter.Postprint (published version

Capacitorless DC–DC regulator as a candidate topology for photovoltaic solar facilities

Postprint (published version

Output-capacitorless low-dropout regulator for power management applications

This article aims to present the design of a 4.5-V, 450-mA low drop-out (LDO) voltage linear regulator based on a two-stage cascoded operational transconductance amplifier (OTA) as error amplifier. The aforementioned two-stage OTA is designed with cascoded current mirroring technique to boost up the output impedance. The proposed OTA has a DC gain of 101 dB under no load condition. The designed reference voltage included in the LDO regulator is provided by a band gap reference with the temperature coefficient (T¿) of 0.025 mV/ºC. The proposed LDO regulator has a maximum drop-out voltage of 0.5 V @ 450 mA of load current, and has the worst case power supply rejection ratio (PSRR) of [54.5 dB, 34.3 dB] @ [100 Hz, 10 kHz] in full load condition. All the proposed circuits are designed using a 0.35 µm CMOS technology. The design is checked in order to corroborate its performance for wide range of input voltage, founding that the circuit design works fine meeting all the initial specification requirements.Postprint (published version

Design of an output-capacitorless low-dropout regulator for power management applications

This article aims to present the design of a 4.5-V, 450-mA low drop-out (LDO) voltage linear regulator based on a twostage cascoded operational transconductance amplifier (OTA) as error amplifier. The aforementioned two-stage OTA is designed with cascoded current mirroring technique to boost up the output impedance. The proposed OTA has a DC gain of 101 dB under no load condition. The designed reference voltage included in the LDO regulator is provided by a band gap reference with the temperature coefficient (T¿) of 0.025 mV/ºC. The proposed LDO regulator has a maximum drop-out voltage of 0.5 V @ 450 mA of load current, and has the worst case power supply rejection ratio (PSRR) of [54.5 dB, 34.3 dB] @ [100 Hz, 10 kHz] in full load condition. All the proposed circuits are designed using a 0.35 µm CMOS technology. The design is checked in order to corroborate its performance for wide range of input voltage, founding that the circuit design works fine meeting all the initial specification requirements.Postprint (published version

Efficient LDO-Assisted DC/DC buck converter for integrated power management system

DC-DC Switching Converters; Voltage Linear Regulators; Linear-Assisted DC-DC Voltage Regulators.Postprint (published version

Linear–Assisted DC/DC Converters with Modified Current-Mode Control Applied to Photovoltaic Solar Systems

Los convertidores DC/DC asistidos linealmente (linear-assisted DC/DC converters) son estructuras que permiten aprovechar las ventajas de las dos alternativas clásicas en el diseño de sistemas de alimentación: reguladores de tensión lineales (ya sean éstos con topología clásica NPN o del tipo LDO –baja tensión de dropout–), y convertidores DC/DC conmutados. En este trabajo se muestra la propuesta de un control de un ciclo en modo corriente modificado (modified current-mode one-cycle control technique) para convertidores DC/DC conmutados asistidos linealmente. Se propone esta técnica de control de un ciclo en modo corriente modificado con el fin de obtener el ciclo de trabajo del interruptor del convertidor conmutado. La estructura propuesta puede proporcionar una salida con adecuadas regulaciones de carga y de línea. El trabajo muestra el diseño de las propuestas del regulador DC/DC asistido linealmente, así como los resultados de simulación que validan la propuesta presentada en el artículo.Peer Reviewe

Current-Steering Switching Policy for a SIDO Linear-Assisted Hysteretic DC/DC Converter

This paper proposes the use of linear-assisted switching power converters in the context of single-inductor dual-output (SIDO) applications. By combining a DC/DC ripplecontrolled switching power converter with the respective voltage linear regulators at each output, improved performance in terms of load and line regulations is obtained. To achieve that aim, a current-steering switching policy is proposed, together with a resource-aware circuit implementation. The ripple-based hysteretic control results in variable switching frequency to guarantee critical conduction mode (boundary of CCM and DCM).Postprint (published version

On single-input dual-output (SIDO) DC/DC multi-port converters for DC microgrid applications

This paper proposes the use of linear-assisted switching power converters in the context of single-inductor dual-output (SIDO) for microgrids (MG) applications. By combining a DC/DC ripple-controlled switching power converter with the respective voltage linear regulators at each output, improved performance in terms of load and line regulations is obtained. To achieve that aim, a current-steering switching policy is proposed, together with a resource-aware circuit implementation. The ripple-based hysteretic control results in variable switching frequency to guarantee critical conduction mode (boundary of CCM and DCM).Peer ReviewedPostprint (published version

Current–Mode One-Cycle control applied to linear–assisted DC/DC converters

This article shows the proposal of an current-mode one-cycle control for linear-assisted DC/DC converters. Linear-assisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators (classic NPN topology or LDO –low dropout–) and switching DC/DC converters. The current-mode one-cycle control technique is proposed in order to obtain the duty cycle of the linear-assisted converter switch. The proposed structure can provide an output with suitable load and line regulations. The paper shows the design and simulation results of the proposed current-mode one-cycle linearassisted converter.Postprint (published version