STMicroelectronics L6902D Manuals

The L6902D is a complete and simple step down switching regulator with adjustable current limit. Based on a voltage mode structure it integrates a current error amplifier to have a constant voltage and constant current control. By means of an on board current sense resistor and the availability of the current sense pins (both compatible to Vcc and for Cs- compatible with GND too) a current limit programming is very simple and accurate (±5%). Moreover constant current control can be used to charge NiMH and NiCd batteries. The device can be used as a standard DC/DC converter with adjustable current limit (set by using the external sense resistor). The internal robust P-Channel DMOS transistor with a typical of 250mΩ assures high efficiency and a minimum dropout even at high output current level. The internal limiting cur

The L6902D evaluation board integrates the step-down switching regulator with adjustable current limit L6902D as well as the external components required for a typical application. The input voltage of the application board can range from 8V up to 25V due to the rated voltage of the input capacitor and the schottky rectifier repetitive peak reverse voltage (both 25V). The external resistor divider (R1 and R2) sets the output voltage of the application board to 3.3V. A different output voltage can be regulated from 1.235V up to 10V, which is the rated voltage of the output capacitor. A current limit of 1A is programmed by the 100mΩ sense resistor Rsense. The inductor saturation current and the forward current of the schottky rectifier fit the current limit setting.