ISL6564A
Multiphase PWM Controller with Linear 6-Bit DAC Capable of Precision r_DS(ON) or DCR Differential Current Sensing

Key Features

• Precision Multiphase Core Voltage Regulation
• Differential Remote Voltage Sensing
• ±0.5% System Accuracy
• Adjustable Reference-Voltage Offset
• Precision r_DS(ON) or DCR Current Sensing
• Accurate Load-Line Programming
• Accurate Channel-Current Balancing
• Differential Current Sense
• Low-Cost, Lossless Current Sensing
• Internal Shunt Regulator for 5V or 12V Biasing
• Microprocessor Voltage Identification Input
• Self Clocked Dynamic VID™ Control Technology
• 6-Bit VID Input
• 0.525V to 1.300V in 12.5mV Steps
• Threshold-Sensitive Enable Function for Power Sequencing Control
• Overcurrent Protection
• Overvoltage Protection
• No Additional External Components Needed
• OVP Pin to Drive Crowbar Device
• 1, 2, 3, or 4 Phase Operation
• Up to 1.5MHz Per Phase Operation (>6MHz Ripple)
• QFN Package
• Compliant to JEDEC PUB95 MO-220 QFN - Quad Flat No Leads - Product Outline
• QFN Near Chip Scale Package Footprint; Improves PCB Efficiency, Thinner in Profile
• Pb-Free Plus Anneal Available (RoHS Compliant)

Description

The ISL6564A is a Multiphase PWM controller which controls microprocessor core voltage regulation by driving up to 4 synchronous-rectified buck channels. It features a high bandwidth control loop to provide optimal response to the load transients. With switching frequency up to 1.5MHz per phase, the ISL6564A based voltage regulator requires minimum components and PCB area in DC/DC converter application.

The ISL6564A senses current by utilizing patented techniques to measure the voltage across the on resistance, rDS(ON), of the lower MOSFETs or DCR of the output inductor during their conduction intervals. Current sensing provides the needed signals for precision droop, channelcurrent balancing, and overcurrent protection.

A unity gain, differential amplifier is provided for remote voltage sensing. Any potential difference between remote and local grounds can be completely eliminated using the remote-sense amplifier. Eliminating ground differences improves regulation and protection accuracy. The thresholdsensitive enable input is available to accurately coordinate the start up of the ISL6564A with any other voltage rail. Dynamic-VID™ technology allows seamless on-the-fly VID changes. The offset pin allows accurate voltage offset settings that are independent of VID setting. The ISL6564A uses a 5V bias and has a built-in shunt regulator to allow 12V bias using only a small external limiting resistor.