The ISL6522 provides complete control and protection for a DC-DC converter optimized for high-performance microprocessor applications. It is designed to drive two N-Channel MOSFETs in a synchronous rectified buck topology. The ISL6522 integrates all of the control, output adjustment, monitoring and protection functions into a single package. The output voltage of the converter can be precisely regulated to as low as 0.8V, with a maximum tolerance of ±1 over temperature and line voltage variations.

The ISL6522 provides simple, single feedback loop, voltage mode control with fast transient response. It includes a 200kHz free-running triangle-wave oscillator that is adjustable from below 50kHz to over 1MHz. The error amplifier features a 15MHz gain-bandwidth product and 6V/µs slew rate which enables high converter bandwidth for fast transient performance. The resulting PWM duty ratio ranges from 0–100.

The ISL6522 protects against overcurrent conditions by inhibiting PWM operation. The ISL6522 monitors the current by using the rDS(ON) of the upper MOSFET which eliminates the need for a current sensing resistor.

Features

• Drives two N-Channel MOSFETs

• Operates from +5V or +12V input

• Simple single-loop control design

- Voltage-mode PWM control

• Fast transient response

- High-bandwidth error amplifier

- Full 0–100 duty ratio

• Excellent output voltage regulation

- 0.8V internal reference

- ±1 over line voltage and temperature

• Overcurrent fault monitor

- Does not require extra current sensing element

- Uses MOSFETs rDS(ON)

• Converter can source and sink current

• Small converter size

- Constant frequency operation

- 200kHz free-running oscillator programmable from 50kHz to over 1MHz

• 14-lead SOIC and TSSOP package and 16-lead 5x5mm QFN Package

• QFN Package

- Compliant to JEDEC PUB95 MO-220 QFN-Quad Flat No Leads-Product Outline.

- Near Chip-Scale Package Footprint; Improves PCB Efficiency and Thinner in Profile

• Pb-free plus anneal available (RoHS compliant)

Applications

• Power supply for Pentium®, Pentium Pro, PowerPC® and AlphaPC™ microprocessors

• High-power 5V to 3.xV DC-DC regulators

• Low-voltage distributed power supplies