Multi-channel Driver Research Articles

A Magnetic Isolation Multichannel Driver With a Wide Range of Pulsewidths for Pulse Generators

A Magnetic Isolation Multichannel Driver With a Wide Range of Pulsewidths for Pulse Generators

An Extendable Half-Bridge Dimmable Multi-Channel LED Driver for DC/DC Grid lighting Applications

In this paper, a light emitting diode (LED) driver with multiple outputs, suitable to use with DC grid supply, is proposed. The proposed LED driver provides the ability to individually control the brightness of each output channel. In order to control the output power of each channel, a burst control mode is employed resulting in reduction of conduction losses. Moreover, the half bridge switches are turned on and off at zero voltage (ZV) with a fixed switching frequency; therefore, the switching losses is reduced and efficiency is further increased. Design and implementation have been simplified by choosing the same structure of the resonant series for outputs. A two-channel DC/DC converter is simulated and tested to verify the theoretical analyses.The presented converter operates above resonant frequency to decrease total harmonic distortion and reduce the size and weight of the components. Therefore, it is suitable for high power application of multi-channel drivers.

CMOS-Photonics Codesign of an Integrated DAC-Less PAM-4 Silicon Photonic Transmitter

Codesign and integration of optical modulators and CMOS drivers is crucial for high-speed silicon photonic (SiP) transmitters to reach their full potential for low-cost, low-power electronic-photonic integrated systems. We present a CMOS-driven SiP multi-level optical transmitter implemented using a commercially available lateral p-n junction process. It uses a Mach-Zehnder modulator (MZM) segmented to increase speed and to lower the required power on a per segment basis to a level achievable with CMOS. A multi-channel driver is designed and implemented in 130 nm RF CMOS, providing a swing of 4 V in a push-pull configuration at 20 Gbaud. Binary data at the CMOS input is manipulated via digital logic to produce the proper per-segment drive signals to generate a four-level pulse-amplitude modulation optical signal. Multi-level modulation is achieved using only binary signals as input (DAC-less). Cosimulation of the optical and electrical circuits shows good agreement with experiment. Reliable transmission is achieved without post-compensation at 28 Gb/s, and at 38 Gb/s when using post-compensation.

Fully integrated multi-channel inductive load driver for harsh automotive applications

The paper addresses the problem of inductive load drivers for automotive applications. The design integrates single-chip in a 0.35 μm low-cost HVMOS technology both the digital circuitry for control and communication with SPI/CAN vehicle networks and the multi-channel drivers optimized for inductive loads. To face ISO26262 requirements also a diagnostic block is embedded. As proved by experimental measurements on fabricated test-chip each channel can sustain up to 650 mA DC current, 1.1 A pulsed current with clamped energy up to 100 mJ, being compliant with automotive harsh operating conditions of ESD up to 4 kV and temperature range from ź40 to 150 °C.

Development of Digital Flow Control System for Multi-Channel Variable-Rate Sprayers

Abstract. Precision modulation of nozzle flow rates is a critical step for variable-rate spray applications in orchards and ornamental nurseries. An automatic flow rate control system activated with microprocessors and pulse width modulation (PWM) controlled solenoid valves was developed to control flow rates of multi-channel nozzles independently for variable-rate sprayers. The system consists of a data acquisition module, a data processing module, and a flow rate control module. An embedded computer along with a touch screen was used to process control algorithms and allowed communication between the sprayer operator and the control system. The flow rate control module was designed with multi-channel driver circuits for activating the solenoid valves and driver protection circuits for avoiding surge voltages due to frequent on/off actions of the solenoid valves. Laboratory tests were conducted to verify the accuracy of the control system with three nozzles (0.530 to 1.703 L min -1 ) at four different operating pressures (138 to 345 kPa) and ten duty cycles (10% to 100%). The microcontroller-controlled circuit precisely produced PWM signals with desired pulse widths to match the duty cycles, and linear spray outputs were achieved accurately with the duty cycles of the PWM-controlled solenoid valves. With the protection circuit for the solenoid valve drivers, the longevity of the solenoid valves increased from 350 to 2,426 h. The system offers flexibility in choosing the number of connection channels needed for the number of nozzles individually or in a group on sprayers. Accordingly, together with canopy structures and travel speeds from laser scanning or other sensors, this compact control system is capable of performing variable flow rate functions for multiple nozzles separately.

Cascaded electro-optic scanning of laser light over large angles using domain microengineered ferroelectrics

We present a device concept based on cascaded electro-optic deflection in a domain microengineered ferroelectric chip. In our design, large deflection angles are achieved by cascading several smaller scanners in a single ferroelectric chip, such that each successive scanner stage builds upon the deflection of the previous stage. We demonstrate the basic concept using a two-stage device fabricated in a single crystal wafer of ferroelectric LiTaO3. By operating the device using a specially designed programmable multichannel driver that provides ±1.1 kV per stage, a total scan angle of 25.4° at 5 kHz was demonstrated. Even larger angles of deflection are possible with additional scanner stages.