Due to market price fluctuations, if you need to purchase or consult the price. You can contact us or emial to us:   sales@allicdata.com

Introduction

The ISL8841AAUZ is an adjustable frequency, synchronous Buck PWM controller that has been designed to operate from an input voltage of 4.5V to 16V, allowing it to be used as a controller for DC/DC converters. It provides four modes of operation, Off Mode, Burst Mode, Discontinuous Mode, and Continuous Mode. Its on-chip logical functions include low voltage lockout, reset, under-voltage lockout, cycle-by-cycle current limiting, over-current protection and soft start. In addition, it can be used with a wide range of protection circuits, such as over temperature, output over-voltage, turn-on time-out, and brown-out protection.

Features and Benefits

• Adjustable PWM frequency between 100kHz and 1MHz
• Integrated power-on reset circuit
• Four mode selections for optimal efficiency, current limiting and start-up sequencing
• On-chip soft start for power-on sequencing
• Programmable dead-time up to 120ns
• Supports up to 60V output voltage
• Compact SOT23-5 package

Application Field

The ISL8841AAUZ is an ideal choice for a wide range of DC-DC applications, such as notebook computers, netbooks, tablets and other mobile products. It is also suitable for automotive and industrial applications, as well as desktop PCs and other high-end systems. This device can be used to power point-of-load and digital power applications, as well as to provide power for low voltage CPUs, FPGAs, DSPs and memory, without the need for an external linear regulator. It is compatible with a variety of topologies, including: synchronous sensorless Buck and Boost, non-synchronous Buck and Boost, and active clamp & soft start.

Working Principle

The ISL8841AAUZ is a Pulse Width Modulated (PWM) controller that uses synchronous rectification to generate the output voltage. It consists of the main regulator circuit, which consists of an oscillator and error amplifier, as well as an over-current protection circuit. The main regulator circuit is designed to enable tight voltage control by keeping the current waveform in the output steady, while the overcurrent protection circuit is designed to shut down the circuit in the event that the output current exceeds a certain level.

The controller works by comparing the voltage from the error amplifier’s output to a reference voltage, and then using the resulting signal to drive a logic circuit that pulses the gate of the upper and lower MOSFETs in order to switch them on and off. The pulse width of these pulses is determined by an internal oscillator, which can be programmed to a frequency between 100kHz and 1MHz. During each cycle, the current through the power MOSFETs is monitored to ensure that the current never exceeds the desired level, thus enabling tight voltage control. Furthermore, the controller also features a soft-start circuit, which is designed to gradually raise the output voltage to the desired level, and a reset circuit, which is designed to reset the system in the event of an over-current condition.

Conclusion

The ISL8841AAUZ is an excellent choice for a multitude of DC-DC applications and provides a high degree of precision, stability and programmability. It is equipped with multiple protection circuits and is capable of providing exceptional performance in a wide range of operating conditions. This device is also highly versatile and can be used with a variety of topologies, making it an ideal solution for many applications.

The specific data is subject to PDF, and the above content is for reference