This 1A synchronous buck converter has the wide input voltage range, high efficiency and low stand-by current required in designs powered by a single-cell lithium-ion battery, ams says.
The AS1382 step-down converter operates from an input range of 2.7-5.5V, and provides an output down to as little as 0.6V. Offering efficiency as high as 96% and no-load current of 95 µA, the converter helps designers of li-ion battery powered devices to reduce losses in the power circuit and to extend their product’s run-time between charges. In shut-down mode, the device draws 0.04µA.
Housed in a 1.22 x 0.85 mm six-lead chip-scale package (WL-CSP6) with a 0.4 mm pitch, the AS1382 operates at an internally fixed frequency of 2 MHz, 3 MHz or 4 MHz, enabling the use of a small inductor. The AS1382 has variants offering a fixed output of 1.0V, 1.2V, 1.5V or 1.8V, and a version with an output adjustable over the range 0.61-3.35V. All support a continuous load current of 1A, and require an output capacitor of 10 µF.
The step-down converter may be operated in one of two modes: its Low-Ripple/Low-Noise mode produces very low levels of ripple and noise. In High-Efficiency mode, the device has lower power losses when supplying light loads, increasing stand-by time in always-on battery operation.
The device includes an internal synchronous switch, which eliminates the need for an external Schottky diode.
The DC-DC step-down converter AS1382 is priced at $0.21 (1000). An evaluation board for the AS1382 is available online.