ZXSC100 Datasheet | Zetex Semiconductors

SINGLE CELL DC-DC CONVERTER SOLUTION DESCRIPTION The ZXSC100 series is designed for DC-DC applications where step-up voltage conversion from very low input voltages is required. These applications mainly operate from single nickel cadmium or nickel metal hydride battery cells. The ZXSC100 devices are non-synchronous PFM, DC-DC controller ICs which drive an external transistor. Zetex Super SOT4™ switching transistors, with saturation resistance as low as 13m Ω, are remended as the external switching element. These bipolar transistors are the best switching devices available for this type of DC-DC conversion, enabling high efficiency conversion with input voltages down to below 1 volt. The circuit can start up under full load with regulation maintained down to an input voltage of only 0.926 volts. The solution configuration ensures optimum Features - - Super SOT4™ switching transistor ZXT14N20DX:VCE(sat) 45m V max @ 1A load Efficiency maintained over a wide range of input voltages and load currents 82% efficiency @ VBATT=1V Startup under full load Minimum operating input voltage VBATT=0.926V Adjustable output voltage down to VBATT Quiescent current typically 150µA referred to input voltage MSOP8 Package SO8 Package Demonstration boards available U1 EM VDRIVE ISENSE FB GND BAS RE VCC efficiency over a wider range of load currents, several circuit configurations are possible with power dissipation up to 2W. The step up output voltage is easily programmed with external resistors, the non-synchronous architecture and Super SOT4™ device enabling an output voltage down to the input voltage level. For best performance the ZXSC100 quiescent current is a small 150µA ensuring minimum battery drain in no load conditions. For the best in space saving the ZXSC100 is offered in the MSOP8 package, however the devices are also available in SO8 packaging for applications where space saving is not so critical. The IC and discrete bination offers the ultimate cost vs...