ISL6431 - Advanc...

  • 2022-09-24 23:33:15

ISL6431 - Advanced Pulse Width Modulation (PWM) Controller for Home Gateway...

The ISL6431 is a high efficiency, fixed frequency, synchronous buck PWM controller. It is designed for core processor, memory and peripheral power supplies required for set-top boxes, cable modems, DSL modems and residential home gateways for applications that use lower distributed voltages to convert to 5V. This device implements a simple working DC-DC buck converter with complete control and protection schemes. Designed to drive N-channel MOSFETs in a synchronous buck topology, the ISL6431 integrates control, output regulation, monitoring and protection functions into a single 8-pin package. The ISL6431 provides simple single feedback loop, voltagemode control with fast transient response. The output voltage can be precisely regulated down to 0.8V, with a maximum tolerance over temperature and line voltage of ±1.5% voltage variation. Fixed frequency oscillators reduce design complexity while balancing cost and efficiency for typical applications. The error amplifier features a 15MHz gain bandwidth product and 6V/µs slew rate, enabling high switching bandwidth for fast transient performance. The resulting PWM duty cycle ranges from 0% to 100%. Provides protection under overcurrent conditions by monitoring the RDS(ON) of the upper MOSFET to suppress PWM operation properly. This method simplifies the implementation and improves efficiency by eliminating the need for a current sense resistor.