SI9105

Si9105 Vishay Siliconix 1-W High-Voltage Switchmode Regulator FEATURES D CCITT Compatible D Current-Mode Control D Low Power Consumption (less than 5 mW) D 10- to 120-V Input Range D 200-V, 250-mA MOSFET D Internal Start-Up Circuit D Current-Mode Control D SHUTDOWN and RESET DESCRIPTION The Si9105 high-voltage switchmode regulator is a monolithic BiC/DMOS integrated circuit which contains most of the components necessary to implement a high-efficiency dc/dc converter in ISDN terminals up to 3 watts. A 0.5-mA max supply current makes possible the design of a dc/dc converter with 60% efficiency at 25 mW, therefore meeting the recommended performance under the CCITT I.430 specifications. This device may be used with an appropriate transformer to implement isolated flyback power converter topologies to provide single or multiple regulated dc outputs (i.e., "5 V). The Si9105 is available in both standard and lead (Pb)-free 16-pin wide-body SOIC, 14-pin plastic DIP and 20-pin PLCC packages which are specified to operate over the industrial temperature range of −40 _C to 85 _C. FUNCTIONAL BLOCK DIAGRAM FB COMP DISCHARGE OSC IN OSC OUT Error Amplifier − VREF + 4 V (1%) Ref Gen 2V − + + − 1.2 V BIAS VCC +VIN 8.7 V − + 9.3 V − + Undervoltage Comparator Current Sources To Internal Circuits C/L Comparator Current-Mode Comparator OSC Clock (½ fOSC) R Q S DRAIN −VIN (BODY) VCC SOURCE S Q R SHUTDOWN RESET Document Number: 70003 S-42030—Rev. H, 15-Nov-04 www.vishay.com 1 Si...