High Efficiency, Highly Integrated 8A and 3A Synchronous Buck Regulators

Intersil Corp. recently announced five new highly integrated synchronous buck regulators that step-down 5-V rails to point-of-load (POL) inputs as low as 0.6 V for FPGAs, DSPs, and microprocessors. The ISL8018 delivers up to 8 A of continuous output current from a 2.7-to-5.5-V input supply. In addition, it provides up to 97% efficiency and higher integration than similar devices.

The ISL8003x devices deliver up to 3 A of continuous output current from a 2.7-to-5.5-V input supply and offer up to 95% peak efficiency for delivering general POL conversions. Useful in telecom, cloud computing, industrial, and medical equipment, the ISL8018 provides an innovative SYNCIN and SYNCOUT feature that connects and synchronizes multiple regulators at the same switching frequency in a master/slave configuration using a phase shifting time delay. With the ISL8018’s VSET feature, the voltage output margining can be set at 10% to compensate for output voltage IR drop. The ISET feature provides programmable output current limits to support 8-, 5-, and 3-A applications. This allows customers to leverage one design with smaller inductors for reduced costs and board area. In addition, the ISL8018’s programmable switching frequency from 500 kHz up to 4 MHz enables the use of smaller passive components for faster transient response and further board space savings.

Key features and specifications:

  • High peak efficiency up to 97%
  • Converter occupies less than 97 mm2 of board space
  • ±10% output voltage margining
  • Output voltage is adjustable from 0.6 V to Vin, with a fixed output voltage option
  • External synchronization up to 4MHz, with master-to-slave phase shifting capability
  • Adjustable switching frequency from 500 kHz to 4 MHz, with default at 1 MHz
  • Start-up with pre-bias output, internal soft-start—1 ms or adjustable, internal/external compensation
  • Soft-stop output discharge during disabled
  • Peak current limiting, hiccup mode short circuit protection, and over-temperature protection
  • Adjustable current limit

The ISL8018 8A synchronous buck regulator is available in a 3 mm × 4 mm, 20-lead QFN package and it costs $1.60 in 1,000-piece quantities. The ISL8018DEMO1Z demonstration board costs $20. The full-featured ISL8018EVAL3Z evaluation board is $115.

Source: Intersil Corp.