Dual step-down regulator supports up to 28V input, reduces BOM

Intersil Corp. has just introduced the ISL85033, a dual channel step-down regulator that lowers component count and maximizes design flexibility for high power-density industrial, communications and consumer electronics applications.

It integrates two high-side MOSFETs which can source 3A per channel or current-share 6A on a single two-phase output. A wide 4.5V to 28V input voltage range makes it an ideal solution for intermediate bus generation and point-of-load (POL) regulation.

The device features a precision internal reference supporting output voltages down to 0.8V. The PWM regulator switches at a default frequency of 500kHz and may be user-programmed or synchronized over a 300kHz to 2MHz range, permitting user optimization of conversion efficiency versus inductor size. SYNC-IN and SYNC-OUT signals also permit synchronizing multiple ICs, while eliminating the need for a system clock.

The regulator drives a smooth and monotonic start-up by allowing users to select either internal or externally adjustable soft-start, along with independent, sequential, ratiometric or absolute tracking between outputs. Independent "PowerGood" and "Enable" signals give flexible monitoring and sequencing properties. User selectable in-phase or out-of-phase switching also gives flexibility to maximize input filter requirements over a wide range of input and output voltage combinations.

The ISL85033 may 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 a suitable fit for a wide range of system requirements. To ensure system reliability, the ISL85033 also has overcurrent, undervoltage lockout and thermal overload protection.

Pricing and availability: The ISL85033 is now available in a compact 28-lead TQFN package. Price starts at $3.30 each for 1,000-unit orders.