42V, Dual 4A (IOUT), Synchronous Buck Silent Switcher 2 Provides 94% Efficiency at 2MHz with Ultra-Low EMI Radiation

Linear Technology Corporation, a division of Analog Devices, Inc., introduced the LT8650S, a dual 4A, 42V input synchronous step-down switching regulator. Its unique Silent Switcher® 2 architecture uses four internal input capacitors and two internal BST and one single INTVCC capacitor to minimize thermal ring area. The LT8650S has a very well-controlled switching edge and internal structure and overall ground plane with copper posts instead of bond wires, and its design greatly reduces EMI emissions. This improved EMI performance is insensitive to PCB layout, which simplifies design and reduces risk, even when using two-layer PC boards. With a 2MHz switching frequency, the LT8650S can easily meet the automotive CISPR 25Class 5 peak EMI limit over the entire load range. The device also offers spread spectrum frequency modulation to further reduce EMI levels.

The LT8650S's synchronous rectification provides up to 94.6% efficiency at 2MHz switching frequency. Its 3.0V to 42V input voltage range is ideal for automotive and industrial applications. The internal high-efficiency switch delivers up to 4A of continuous output current and up to 6A of peak load on any channel simultaneously to output voltages as low as 0.8V. The Burst Mode® operation of the LT8650S ensures that only 6.2μA of quiescent current (for both channels) is ideal for applications such as keeping the system on at all times because this type of application requires extended battery life. The LT8650S achieves a fast 2ns switching from 16V input to 2V output with only a fast 40ns minimum turn-on time, allowing designers to optimize efficiency while avoiding critical frequency bands that are sensitive to noise. The LT8650S's 32-pin 4mm x 6mm LQFN package and high switching frequency allow the use of small external inductors and capacitors, resulting in a compact and thermally efficient footprint.

The LT8650SEV is available in a 4mm x 6mm LQFN package. The industrial temperature grade version LT8650SIV is tested and guaranteed to operate within the operating junction temperature range of –40°C to 125°C.

Relevant LT86 series products

Author：Brittany Antonia （The author of article owns the copyright.）