Precision rectifier

About: Precision rectifier is a research topic. Over the lifetime, 4952 publications have been published within this topic receiving 63668 citations. The topic is also known as: super diode.

A 13.56MHz CMOS rectifier with switched-offset for reversion current control

Abstract: A 13.56 MHz full-wave active rectifier for wirelessly powered high-current biomedical implants is presented. It employs switched-offset in reducing the comparator delay for reversion current control. The rectifier was fabricated in a standard 0.35 µm CMOS process with an active area of 0.041 mm2. The measured power conversion efficiency is better than 83% over a wide ac input range (1.5 to 4 V) and load range (5k to 500 Ω), and reaches up to 90% at 3.5 V and 1.8 kΩ.

Class-D Zero-Current-Switching Rectifier as Power-Factor Corrector for Lighting Applications

Abstract: An analysis and design of a zero-current-switching (ZCS) Class-D current-source driven rectifier for the lighting applications is presented, which is one of the resonant rectifiers as a power-factor corrector to improve a poor power-factor and high line current harmonic of a single-stage converter. A high power-factor is achieved by the utilization of output characteristics of a Class-D ZCS rectifier, which is inserted between the front-end bridge rectifier and the bulk-filter capacitor. The conduction angle of the bridge rectifier diode current was increased and a low-line current harmonic and a power-factor near unity can be obtained. The design procedure is based on the principle of the Class-D ZCS rectifier, which also ensures more accurate results and the proposed scheme provides a high efficiency and a more systematic and feasible analysis methodology. The active switches can be operated under the soft-switching condition. The validity of this approach was confirmed by simulation and experimental results.

Synchronization signal separator circuit

Abstract: A synchronization signal separator circuit is provided for separating the synchronizing signal components of a composite video signal. A composite video signal containing negatively-directed synchronizing pulse components is coupled to one input of a differential amplifier comprising two transistors of one conductivity type, and to the base electrodes of a peak detector charging transistor of opposite conductivity type. The charging transistor charges a peak detecting capacitor to a reference level which establishes the slicing level of the sync separator. The base-to-emitter voltage of the charging transistor offsets the slicing level by one V be relative to the sync pulse tips, thereby ensuring that the slicing level is offset from the sync tip level. The peak detecting capacitor is coupled to a second input of the differential amplifier, where the slicing level is compared with the composite video signal for separation of the sync pulses. A current source resistor is also provided, which is the sole source of charging current for the peak detecting capacitor between sync pulse intervals. The charging current allows the slicing level to vary so as to follow changes in video signal level. The sync separator recovery circuit is provided which is keyed to cause the slicing level to change rapidly in response to sudden changes in signal level.

A switched-mode three-phase three-level telecommunications rectifier

Abstract: This paper presents a high power factor three-phase three-level 6 kW rectifier. The rectifier is composed of two stages connected in series: a three-switch three-level pulse-width modulated (PWM) preregulator and a neutral-point-clamped zero-voltage-switching PWM DC-DC converter (NPC-ZVS-PWM). The structures chosen for both stages have a common capacitive center point that allows the three-level operation and a low blocking-voltage stress on all the power switches (half of DC-link voltage). The reduction of blocking voltage allows the use of low cost and low loss power devices, increasing the efficiency and the power density with reduced production cost.

Electric cranking motor automatic disconnect and lockout circuit

Abstract: An electric cranking motor automatic disconnect and lockout circuit. The normally open contacts of a cranking motor solenoid operated switch are connected in series with the electric cranking motor across a source of direct current supply potential. Upon the closure of an electric switch, the source of direct current supply potential, applied across the gate-cathode electrodes of a first silicon controlled rectifier, triggers this device conductive through the anode-cathode electrodes to establish a circuit for base-emitter current flow through a first transistor. The conductive first transistor establishes an energizing circuit for the operating coil of an electric relay which, in turn, establishes an energizing circuit for the operating coil of the solenoid operated switch. The output potential of an electrical generator driven by the cranking motor armature is applied across the gate-cathode electrodes of a second silicon controlled rectifier. When the generator output potential is of sufficient magnitude to produce gate-cathode current through the second silicon controlled rectifier, the resulting anode-cathode current flow therethrough shunts base current from the first transistor to extinguish this device, thereby interrupting the energizing circuit for the operating coil of the electric relay and, in turn, the solenoid operated switch to provide automatic disconnect of the cranking motor upon engine start. A vibration transducer mounted upon the cranked engine produces an alternating current potential signal which triggers a second transistor conductive to shunt gate current from the first silicon controlled rectifier thereby preventing the retriggering of the first transistor while the engine is running to provide a lockout of the cranking motor.