Intersil's New Dual Step-Down Regulator Delivers Efficient, High-Density Power for Industrial, Communications and Consumer Applications

The ISL85033 includes features that maximize performance and efficiency while reducing external component count and improving design flexibility. These include low resistance power MOSFETs optimized for thermal performance up to 3A of output current per channel. In addition, a precision internal reference supports output voltages down to 0.8V. The PWM regulator switches at a default frequency of 500kHz and can be user-programmed or synchronized over a 300kHz to 2MHz range, allowing user optimization of conversion efficiency versus inductor size. SYNC-IN and SYNC-OUT signals allow synchronizing multiple ICs without the need for a system clock.

The regulator enables smooth and monotonic start-up by letting users select either internal or externally adjustable soft-start, along with independent, sequential, ratiometric or absolute tracking between outputs. Independent PowerGood and Enable signals provide flexible monitoring and sequencing capabilities. User selectable in-phase or out-of-phase switching provides flexibility to optimize input filter requirements over a wide range of input and output voltage combinations. The ISL85033 can be configured in various operating modes such as a dual 3A step-down regulator, single 6A current-share step-down regulator and negative output buck-boost regulator, making it an ideal fit for a wide range of system requirements. To ensure system reliability, the ISL85033 includes overcurrent, undervoltage lockout and thermal overload protection.