SC1185A Datasheet | SEMTECH

Description The SC1185 bines a synchronous voltage mode controller with two low-dropout linear regulators providing most of the circuitry necessary to implement three DC/ DC converters for powering advanced microprocessors such as Pentium® II . The SC1185 switching section Features an integrated 5 bit D/A converter, pulse by pulse current limiting, integrated power good signaling, and logic patible shutdown. The SC1185 switching section operates at a fixed frequency of 140k Hz, providing an optimum promise between size, efficiency and cost in the intended application areas. The integrated D/A converter provides programmability of output voltage from 2.0V to 3.5V in 100m V increments and 1.30V to 2.05V in 50m V increments with no external ponents. The SC1185 linear sections are low dropout regulators supplying 1.5V for GTL bus and 2.5V for non-GTL I/O. The Reference voltage is made available for external linear regulators. Typical Application Circuit SC1185 & SC1185A Programmable Synchronous DC/DC Converter, Dual LDO Controller Features Synchronous design, enables no heatsink solution 95% efficiency (switching section) 5 bit DAC for output programmability On chip power good function Designed for Intel Pentium® ll requirements 1.5V, 2.5V @ 1.25% for linear section 1.265V ± 1.5% Reference available 24-lead SO package. Lead free option available. Lead free product is fully WEEE and Ro HS pliant. Applications Pentium® ll microprocessor supplies Flexible motherboards 1.3V to 3.5V microprocessor supplies Programmable triple power supplies 12V 5V 1500u F x4 + 0.1u F + 4.7u F PWRGOOD VID0 VID1 VID2 VID3 VID4 EN 3.3V 0.1u F 5 VCC 7 PWRGOOD CS+ CS- 9 8 0.1u F 22 VID0 VOSENSE 17 IRLR3103N 21 VID1 20 VID2 BSTH 15 DH 11 2R2 19...