STMicroelectronics’ New Voltage Regulator Shrinks Portable and Battery-Powered Devices
STMicroelectronics Inc. introduced a high-frequency step-down dc-dc converter particularly suited for use in data-storage applications, such as hard disk drives, DVDs, Blu-ray Discs, High-Definition DVDs, and in portable devices, such as MP3 players and digital cameras, that require high efficiency, small size, and light weight. The new, cost-competitive ST1S06 integrates functions that benefit users with effiecient electrical performance while minimizing the need for external components.
An advance over the previous ST1S03 and ST1S03A switching voltage regulators, the new ST1S06 includes a synchronous rectification block to avoid the use of an external Schottky Diode while improving the device's efficiency up to 95%.
Other key features of the ST1S06 include an output current capability of 1.5A maximum over all operating conditions, a high switching frequency of 1.5MHz and great stability, allowing a drastic reduction in Printed Circuit Board (PCB) area. In fact, the high frequency performance allows the device to operate with a small inductor, while the high stability permits the use of small, low-ESR, ceramic capacitors. As a result, the ST1S06 requires only a few external components to operate: the small inductor, two capacitors and, for the adjustable version, two resistors.
The device provides a soft-start, which prevents inrush current and minimizes start-up problems in battery-powered devices. Additionally, the ST1S06 is available with fixed output voltages or in the adjustable version that, using an external resistor divider, generates an output voltage adjustable from 0.8V feedback voltage.
Built using ST's proprietary BCD6 smart-power technology, the ST1S06 is designed in Italy and South China, diffused in the US, and assembled in Malaysia. The device is offered in two versions: with and without an enable feature. Both versions are available in the tiny DFN6 3x3mm ECOPACK® package. The voltage regulator can be combined with several codified versions of a demo board for evaluation purposes. In production now, pricing ranges from $0.35 to $0.45 in very high volume.
