Date: 02/10/2009
Semtech expand its high-efficiency synchronous buck controller platform
Semtech has announced the expansion of its high efficiency buck (step down) controllers with addition of the SC418 and SC419 platform products. The SC419 is intended for operation in systems that have dual supplies, while the SC418 integrates a low dropout (LDO) regulator to enable operation from a single supply up to 28V. Both devices feature strong gate drives (2A high side, 4A low side), and are optimized for low EMI and high efficiency over an extended load range.
The key features of the SC418 and SC419 controllers are,
Operating input voltage range from 3V to 28V
Programmable 150mA LDO can be used to provide gate drive bias for a single rail solution (SC418)
SmartDrive reduces EMI and eliminates the need for snubbers or gate drive resistors
Automatic LDO crossover circuitry optimizes efficiency for VOUT = VLDO (SC418)
Selectable continuous conduction mode, regular power save, and programmable frequency ultrasonic power save (patent pending)
Fully protected - built-in soft-start, cycle-by-cycle current limiting, over-temperature, over-voltage and under-voltage protection features. They also include a power good output for the switching regulator, which may be used for diagnostics and sequencing.
The Smart Power Save technique enables the SC418 to re-enter continuous conduction mode when active loads to pull the output high while in power save mode, pulling the output back down and avoiding over voltage latch-off.
"The SC418 and SC419 take the same sophisticated architecture embedded in our SC414 and SC417 integrated regulators and provide the user with a flexible, efficient controller that can be used to optimize solutions for a wide range of applications," said Alan Burchfield, Senior Product Marketing Manager for Semtech's Power Management Group. "This device is packed full of features that optimize efficiency, minimize noise and make it as easy as possible for engineers to use."
Pseudo fixed frequency adaptive on-time control gives the parts superior transient response while reducing the output filter capacitance required and simplifying the design process by removing external compensation components. The controller can be readily set up to allow output voltages up to 12V, will support full ceramic output capacitor solutions, and will start up into a pre-biased output. The strong gate drives provide enough current to power a single-phase solution up to 30A.
Package: Compact ultra-thin 3mm x 3mm Pb-free, halogen-free, RoHS/WEEE compliant package
Price:
SC418: Each $0.86 for 3k pieces
SC419: Each $0.79 for 3k pieces
Availability: Now
For more details visit www.semtech.com