DN68 ZXSC310 High power torch reference design Description This design note shows a typical ZXSC310 LED driver circuit for a high powered LED torch. The input voltage ranges from 0.7V to 1.6V with a maximum output current of 335mA at 1.4V input. A typical schematic diagram is shown in Figure 1. D1 L1 VIN U1 Q1 Vcc Vdrive C1 C2 Stdn C3 Isense Gnd ZXSC310 Figure 1 R1 Schematic diagram Reference Value Part number Manufacturer Contact details Comments U1 ZXSC310E5 Zetex www.zetex.com LED driver in SOT23-5 Q1 FMMT617 Zetex www.zetex.com Low sat. NPN in SOT23 Zetex www.zetex.com 2A Schottky in SOT23 D1 2A ZHCS2000 L1 7.5H DO3316P-153x2 Coilcraft R1 19.5m⍀ Generic Generic NA C1 1F Generic Generic NA C2 220F Generic Generic NA C3 100F Generic Generic NA Table 1 Issue 2 - July 2006 © Zetex Semiconductors plc 2006 www.coilcraft.com ISAT = 3A 0805 size Bill of materials 1 www.zetex.com DN68 Figure 2 Performance graphs Europe Americas Asia Pacific Corporate Headquarters Zetex GmbH Streitfeldstraße 19 D-81673 München Germany Zetex Inc 700 Veterans Memorial Highway Hauppauge, NY 11788 USA Zetex (Asia Ltd) 3701-04 Metroplaza Tower 1 Hing Fong Road, Kwai Fong Hong Kong Zetex Semiconductors plc Zetex Technology Park, Chadderton Oldham, OL9 9LL United Kingdom Telefon: (49) 89 45 49 49 0 Fax: (49) 89 45 49 49 49 [email protected] Telephone: (1) 631 360 2222 Fax: (1) 631 360 8222 [email protected] Telephone: (852) 26100 611 Fax: (852) 24250 494 [email protected] Telephone: (44) 161 622 4444 Fax: (44) 161 622 4446 [email protected] For international sales offices visit www.zetex.com/offices Zetex products are distributed worldwide. For details, see www.zetex.com/salesnetwork This publication is issued to provide outline information only which (unless agreed by the company in writing) may not be used, applied or reproduced for any purpose or form part of any order or contact or be regarded as a representation relating to the products or services concerned. The company reserves the right to alter without notice the specification, design, price or conditions of supply of any product or service. www.zetex.com 2 Issue 2 - July 2006 © Zetex Semiconductors plc 2006