ISL6529
Dual Regulator-Synchronous Rectified Buck PWM and Linear Power Controller

Key Features

• Provides two regulated voltages
• One synchronous rectified buck PWM controller
• One linear controller
• Both controllers drive low cost N-Channel MOSFETs
• 12V direct drive saves external components
• Small converter size
• 600kHz constant frequency operation
• Small external component count
• Excellent output voltage regulation
• Both outputs: ±1% over temperature
• ISL6529AC-Both outputs: ±2% over temperature - ISL6529C
• 5V down conversion
• PWM and linear output voltage range: down to 0.8V
• Simple single-loop voltage-mode PWM control design
• Fast PWM converter transient response
• High-bandwidth error amplifier-Full 0
• 100% duty ratio
• Linear controller drives N-Channel MOSFET pass transistor
• Fully-adjustable outputs
• Undervoltage fault monitoring on both outputs
• QFN Package:
• Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat No Leads - Package Outline
• Near Chip Scale Package footprint, which improves PCB efficiency and has a thinner profile
• Pb-Free Available (RoHS Compliant)

Description

The ISL6529, ISL6529A provide the power control and protection for two output voltages in high-performance graphics cards and other embedded processor applications. The dual-output controllers drive two N-Channel MOSFETs in a synchronous rectified buck converter topology and one N-Channel MOSFET in a linear configuration. The ISL6529, ISL6529A provide both a regulated high current, low voltage supply and an independent, lower current supply integrated in a 14-lead SOIC package. The controllers are ideal for graphic card applications where regulation of both the graphics processing unit (GPU) and memory supplies is required.

The synchronous rectified buck converters incorporate simple, single feedback loop, voltage-mode control with fast transient response. Both the switching regulator and linear regulator provide a maximum static regulation tolerance of ±2% over line, load, and temperature ranges. Each output is user-adjustable by means of external resistors.

An integrated soft-start feature brings both supplies into regulation in a controlled manner. Each output is monitored via the FB pins for undervoltage events. If either output drops below 51.5% of the nominal output level, both converters are shut down.

Applications

• Graphics - GPU and memory supplies
• ASIC power supplies
• Embedded processor and I/O supplies
• DSP supplies