EVAL6902D STMicroelectronics

EVAL6902D L6902D 1A Constant current battery charger evaluation board Data Brief General description 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 Evaluation board output capacitor. A current limit of 1A is programmed by the 100m sense resistor R . sense The inductor saturation current and the forward current of the schottky rectifier fit the current limit setting. October 2006 Rev 1 1/4 For further information contact your local STMicroelectronics sales office. www.st.com 4EVAL6902D Figure 1. Application test circuit L1 V OUT IN VCC Rsense V OUT VREF D1 CS+ R1 COMP L6902D CS- C1 C4 C2 FB C3 R2 R3 GND Figure 2. Package Table 1. Demoboard part list Name Value P/N Manufacturer Notes C1 10F C4532X5R1E106M TDK C2 100F 10TPB100M POSCAP D1 STPS2L25U ST L1 22H DO1813HC-223 COILCRAFT Device L6902D ST R1 8.2 k 0603, 1% R2 3.3 k 0603, 1% R3 4.7 k 0603, 1% C3 220pF 0603, 50V C4 22nF 0603, 50V R 100m sense 2/4