ISL62871HRUZ-T

The ISL62871HRUZ-T is a single pulse width modulation (PWM) mode, DC-DC switching controller with high-side precharged synchronous rectification that provides an easy-to-design solution for applications from 3.0-12V. It integrates a high-side PFET precharged shunt regulator, a PWM logic control function, an internal current limit circuit and an integrated precision-regulated reference to create a flexible, low cost power converter solution. It is well suited for applications in computers, portable systems and industrial systems.

Application Field

The ISL62871HRUZ-T is a flexible PWM switching controller suitable for a wide range of power conversion design applications from 20W to 40W. It is suitable for use in computer applications such as CPU power supply, LCD display power supply, and rapid charge and discharge power supply of portable equipment. It is also suitable for use in industrial applications such as AC - DC power supply, power cordless tool power supply and battery power applications.

The ISL62871HRUZ-T combines diverse features to make a power system design faster, easier and more efficient. It provides an easy to use, configurable and flexible platform to create a custom designed power supply that meets the needs of a variety of design applications.

Working principle

The ISL62871HRUZ-T is a pulse width modulation (PWM) mode DC-DC switching controller with high-side precharged synchronous rectification. In operation, it samples the input voltage and compares it to the internal precision regulated reference voltage, VREF, via a voltage sense pin, using an internal differential amplifier. When the input voltage is greater than the VREF, the switching FET is turned on and current flows from the input source through to the output capacitor.

When the voltage on the output capacitor reaches the internal VREF voltage, the FET is turned off, causing the current to stop flowing. The equivalent duty cycle of the PWM controller is then compared to the internal VREF voltage, via a current sense pin. This duty cycle maintains an output voltage that is relative to the internal VREF voltage.

Features

The ISL62871HRUZ-T is a low cost, easy to use PWM switching controller. It provides a wide range of features to make power system design easier and faster, including:

• Built-in high-side PFET power switch and precharged synchronous rectification
• Wide input voltage range to accommodate single- and multi-cell Li-ion and alkaline battery applications
• Maximum duty cycle of 96.6%
• Internal precision regulated reference voltage, VREF, ensures stable output voltage
• Controlled output current limit for overload protection
• External switching frequency control capability
• Internal under-voltage lockout (UVLO)
• Programmable soft-start capability
• Pulse by pulse over-current protection
• Thermal shutdown protection
• Low quiescent current: 6.6 μA w/output voltage set to 12V
• Shutdown current: < 10 μA
• Operating temperature range: -40°C to +125°C
• Available in an 8-pin WSON package

Conclusion

The ISL62871HRUZ-T is a single pulse width modulation (PWM) mode, DC-DC switching controller with high-side precharged synchronous rectification that provides an easy-to-design solution for applications from 3.0-12V. It integrates a high-side PFET precharged shunt regulator, a PWM logic control function, an internal current limit circuit and an integrated precision-regulated reference to create a flexible, low cost power converter solution. The ISL62871HRUZ-T provides an easy to use, configurable and flexible platform to create a custom designed power supply that meets the needs of a variety of design applications.