Step-down converters feature ultra-low EMI performance

By Gina Roos, editor-in-chief

Analog Devices Inc. (ADI) has expanded its Silent Switcher series with the introduction of the LT8650S, LT8652S, and LT8653S dual-channel 4-A/8.5-A/2-A synchronous step-down converters targeted at automotive, communications, and solid-state-drive power supply applications. The new Silent Switcher converters leverage ADI’s proprietary Silent Switcher 2 architecture along with spread- spectrum frequency modulation to achieve ultra-low electromagnetic (EMI) performance that meets CISPR25 emissions.

The Silent Switcher 2 architecture integrates bypass capacitors to reduce radiated EMI and delivers ultra-low EMI on any printed circuit board. It also features optional spread-spectrum modulation. (See video for more information on the technology’s low-noise and high-efficiency operation.)

A key differentiator for these products is their stackable-friendly outputs for higher-current applications. Outputs can be paralleled to scale up or down the output current based on system requirements while optimizing thermal performance, said ADI.

For example, the LT8652S provides 8.5-A DC from each channel simultaneously or up to 12 A on either channel. Synchronizing two LT8652S chips can achieve a four-phase, 34-A supply.  “This also helps to minimize inventory and qualification time with a single device,” said ADI. Other features include ultra-low quiescent-current burst mode for light-load operation and an adjustable and synchronizable frequency from 300 kHz to 3 MHz.

Available now, the LT8650S (4 × 6-mm LQFN), LT8652S (4 × 6-mm LQFN), and LT8653S (4 × 3-mm LQFN) are priced, respectively, at $5.75, $4.50, and $4.02.