ISL6540
Single-Phase Buck PWM Controller with Integrated High Speed MOSFET Driver and Pre-Biased Load Capability

Key Features

• VIN and Power Rail Operation from +3.3V to +20V
• Fast Transient Response
• 0 to 100% Duty Cycle
• 15MHz Bandwidth Error Amplifier with 6V/µs Slew Rate
• Voltage-Mode PWM Leading and Trailing-edge Modulation Control
• Input Voltage Feedforward Compensation
• 2.9V to 5.6V High Speed 2A/4A MOSFET Gate Drivers
• Tri-state for Power Stage Shutdown
• Internal Linear Regulator (LR) - 5.6V Bias from VIN
• External LR Drive for Optimal Thermal Performance
• Voltage Margining with Independently Adjustable Upper and Lower Settings for System Stress Testing & Over Clocking
• Reference Voltage I/O for DDR/Tracking Applications
• Precise 0.591V Internal Reference with Buffered Output
• ±0.85%/±1.25% Over Commercial/Industrial Range
• Source and Sink Overcurrent Protections
• Low- and High-Side MOSFET r_DS(ON) Sensing
• Overvoltage and Undervoltage Protections
• Small Converter Size - QFN package
• Oscillator Programmable from 250kHz to 2MHz
• Differential Remote Voltage Sensing with Unity Gain
• Programmable Soft-start with Pre-Biased Load Capability
• Power Good Indication with Programmable Delay
• EN Input with Voltage Monitoring Capability
• Pb-Free Plus Anneal Available (RoHS Compliant)

Description

The ISL6540 is a single-phase voltage-mode PWM controller with input voltage feedforward compensation to maintain a constant loop gain for optimal transient response, especially for applications with a wide input voltage range. Its integrated high speed synchronous rectified MOSFET drivers and other sophisticated features provide complete control and protection for a DC/DC converter with minimum external components, resulting in minimum cost and less engineering design efforts.

The output voltage of the converter can be precisely regulated with an internal reference voltage of 0.591V, and has a system tolerance of ±0.85% over commercial temperature and line load variations. An external voltage can be used in place of the internal reference for voltage tracking/DDR applications.

The ISL6540 has an internal linear regulator or external linear regulator drive options for applications with only a single supply rail. The internal oscillator is adjustable from 250kHz to 2MHz. The integrated voltage margining, programmable pre-biased soft-start, differential remote sensing amplifier, and programmable input voltage POR features enhance the ISL6540 value.

Applications

• Power Supply for some Microprocessors and GPUs
• Wide and Narrow Input Voltage Range Buck Regulators
• Point of Load Applications
• Low-Voltage and High Current Distributed Power Supplies