Buck controllers are said to deliver industry’s fastest transient response and highest system accuracy

The ISL6312, ISL6312A and ISL6322 provide a complete, integrated precision voltage regulation system for advanced Intel VR10/11(Intel Core 2 Duo and Intel Core 2 Extreme) and AMD AM2 5/6-bit microprocessors. The family features programmable VID voltage identification codes for Intel and AMD digital-to-analogue converter tables.

Family variations are available for many popular computing applications. For example, the ISL6312A enables customers to monitor the CPU load current in real-time for improved reliability, while the ISL6322 is optimised specifically to work with overclocking applications such as performance motherboards using Intel’s Core 2 Extreme processor.

The devices use Intersil’s proprietary active pulse positioning (APP) and adaptive phase alignment (APA™) modulation schemes to achieve the industry’s fastest transient response with the fewest output capacitors compared with competitive designs. APP and APA are pulse width and positioning modulation techniques that speed up load transient response and reduce the need for external bulk output capacitors required to supply stored energy to the CPU (central processing unit) during abrupt changes in line voltage and load current.

All three devices incorporate a unity gain differential amplifier for remote voltage sensing that compensates for differences between remote and local grounds. The ISL6312/12A/22 also integrate three MOSFET drivers and a PWM output for a fourth external MOSFET driver.
The ISL6312, ISL6312A and ISL6322 provide advanced control loop features to optimise transient response to load-apply and removal functions. These include highly accurate and fully differential continuous DCR (DC resistance) current sensing for load line programming and channel current balance. These features also ensure individual channel current and average overcurrent protection (OCP).
The devices incorporate key features developed by Intersil specifically for these applications, including active pulse positioning modulation, enabling rapid initial response to high slew rate (di/dt) load transients. The ISL6312/12A/22 also include adaptive phase alignment that enables the fastest possible load transient response with capacitor elimination when there is a severe load turn-on.
The ISL6312A incorporates an added IOUT pin to the basic ISL6312 architecture for output current measurement. The ISL6322 provides an I2C bus input for adjusting four basic regulator functions, such as the output voltage, overvoltage protection (OVP) level, operating frequency per phase, and MOSFET driver adaptive dead time control. The family features sophisticated overvoltage, undervoltage, and overcurrent protection. Additionally, the ISL6312/12A/22 include open circuit protection on the remote sensing inputs.

Target applications for the devices are desktops, workstations, servers, single board motherboards, industrial PC motherboards, routers and switches, and voltage regulator modules.
The ISL6312, ISL6312A, and ISL6322 are available now in space-saving, 48-lead, 7 x 7 QFN packages.