ST provides a wide portfolio of high-performance step-up (boost) switching regulators, with both synchronous and non-synchronous switches and charge pump ICs. Other features include micropower operation with very low supply current, high efficiency, small size, adjustable or synchronizable switching frequencies, and current generators for LED driving.
The ST8R00 is a step-up DC-DC converter featuring an output current cut-off function. This boost converter is ideal for use where designers have tight constraints in terms of PCB area and cost. In demanding applications such as Blu-ray disc players/recorders, laptops and game consoles, the ST8R00 allows significant reductions to be achieved in both the PCB area and the manufacturing cost, without sacrificing performance
LED770x regulators for LED lighting and backlighting
The LED770x family is composed of monolithic, high-efficiency LED drivers intended for arrays used in the backlight of LCD panels in consumer, industrial and automotive applications, and in architectural lighting applications.
Housed in compact QFN packages, the ICs integrate a boost converter and a LED array driver consisting of several PWM-dimmable current generators giving excellent dimming performances, suitable for all LCD backlighting applications.
The boost converter is based on a constant switching-frequency, peak current-mode architecture. The devices keep the lowest row’s voltage regulated at the internal reference voltage, and adapt the boost output voltage to reduce power losses across the current generators. The boost-converter default switching frequency is fixed at about 650 kHz. This is a good compromise in terms of efficiency, size and cost of the power elements and of the overall application, but it can also be set anywhere in the 250 kHz to 1 MHz range by simply connecting an external resistor, if more flexibility is required.
The LED770x family, with an input voltage range from 3.6 or 4.5 V up to the output voltage, covers the most common voltage buses (5 V, 12 V and 24 V). Additional flexibility is guaranteed by a full set of adjustable protection functions, together with complete and flexible fault management, a wide input voltage range and high switching frequency, to reduce the size and cost of the total application.
