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SEMTECH CORP. has expanded its efficient, high-performance EcoSpeed™ regulator platform to include a 3A output current device with a wide input voltage range from 5.5 to 24V. The new SC410 joins Semtech's existing platform of EcoSpeed converters, which includes a broad selection of output current capabilities ranging from 3A to 30A. The wide input voltage range of the SC410 makes it ideal for use with lithium ion battery packs and charging adapters or regulated 12V or 18V main power supply rails in embedded applications for industrial, networking/communications, office automation and higher-end consumer digital electronic products.
The SC410 incorporates Semtech's advanced, patented adaptive on-time (AOT) architecture to achieve best-in-class performance for today's demanding green power requirements by efficiently managing both standby and full current demands. The AOT architecture uses an advanced control loop to dynamically adjust the on-time based on input and output voltages. This results in a pseudo-fixed frequency operation and predictable EMI - comparable to conventional voltage mode and current mode topologies, and better than constant on-time and hysteretic architectures where frequencies are unpredictable.
The AOT architecture controls response time using a fast comparator, instead of a relatively slow error amplifier, as is used in conventional voltage mode and current mode topologies, reducing the size of the power components used in the system. AOT also eliminates the need for loop compensation components and enables the use of ceramic input and output capacitors, simplifying design and reducing component count.
Since the SC410 is programmable from 200kHz to 1MHz, it enables designers to optimize their power supply to maximize either the conversion efficiency or the solution size. The device also includes Semtech's proprietary SmartDrive™ technology, which is a two-step, high-side FET turn-on technology designed to reduce EMI in noise-sensitive applications.
The ultrasonic power save (PSAVE) feature included in the SC410 provides high efficiency across the entire load range by lowering the switching frequency to cater to low-power standby requirements. This reduces power FET gate charge switching losses and results in high standby efficiency during light loads. When the load changes from standby to full load, the EcoSpeed converter cycle-by-cycle response quickly exits PSAVE mode, providing very fast wake-up recovery time. To eliminate audible noise during standby, the ultrasonic PSAVE maintains switching frequencies above 22kHz.
The SC410 EcoSpeed regulator also incorporates soft-start to reduce inrush and minimize stress on the input power source, along with dedicated power-good and enable pins to simplify power supply design. Comprehensive fault protection features include cycle-by-cycle current limit and short circuit, over and under output voltage, and over-temperature protection. The device is packaged in a 10-pin, 3.0 × 3.0 × 1.0 mm, lead-free, halogen-free MLPD package for further space savings.
Camarillo, CA www.semtech.com
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