2.5A Regulator with Integrated High-Side MOSFET for Synchronous Buck or Boost Buck Converter

The ISL85402 is a synchronous buck controller with a 125mΩ high-side MOSFET and low-side driver integrated. The ISL85402 supports a wide input range of 3V to 36V in buck mode. It supports 2.5A continuous load under conditions of 5V VOUT, VIN range of 8V to 36V, 500kHz and +105°C ambient temperature with still air. For any specific application, the actual maximum output current depends upon the die temperature not exceeding +125°C with the power dissipated in the IC, which is related to input voltage, output voltage, duty cycle, switching frequency, board layout and ambient temperature, etc. Refer to “Output Current” on page 14 for more details.

Features

• Buck Mode: Input Voltage Range 3V to 36V (Refer to “Input Voltage” on page 13 for more details)

• Boost Mode Expands Operating Input Voltage Lower Than 2.5V (Refer to “Input Voltage” on page 13 for more details)

• Selectable Forced PWM Mode or PFM Mode

• 300µA IC Quiescent Current (PFM, No Load); 180µA Input Quiescent Current (PFM, No Load, VOUT Connected to AUXVCC)

• Less than 3µA Shut Down Input Current (IC Disabled)

• Operational Topologies

- Synchronous Buck

- Non-Synchronous Buck

- Two-Stage Boost Buck

• Programmable Frequency from 200kHz to 2.2MHz and Frequency Synchronization Capability

• ±1 Tight Voltage Regulation Accuracy

• Reliable Overcurrent Protection

- Temperature Compensated Current Sense

- Cycle-by-Cycle Current Limiting with Frequency Foldback

- Hiccup Mode for Worst Case Short Condition

• 20 Ld 4x4 QFN Package

• Pb-Free (RoHS Compliant)

Applications

• General Purpose

• 24V Bus Power

• Battery Power

• Point of Load

• Embedded Processor and I/O Supplies