SC338(A) Ultra Low Output Voltage Dual Linear FET Controller POWER MANAGEMENT Description Features The SC338(A) is an ultra low output voltage dual power 1.5% and 2.5% reference voltage options supply controller designed to simplify power management available TM for notebook PCs. It is part of Semtechs Smart LDO Two independant and fully adjustable outputs family of products. The SC338(A) has two user Wide supply voltage range permits operation from adjustable outputs that can be set anywhere between 5V or 12V rails 0.5V and 3.3V (V = 12V, anywhere between 0.5V and IN Very low quiescent current (500A typical with both 1.8V for V = 5V) using two external resistors per IN outputs enabled and 5V input) output. Indivdual Enable control for each output Individual Power Good monitoring and signalling for SC338(A) features for each output include tight output each output voltage regulation (2.5% over -40C to +85C for Gate drives from input supply enable use of SC338, 1.5% over 0C to +85C for SC338A), enable N-channel MOSFETs controls, open drain power good signals, under-voltage User selectable dropout voltage protection and soft start. The enable pins allow the part Individual under-voltage protection for each output to enter a very low power standby mode. Pulling them MSOP-10 surface mount package high enables the outputs. The power good pins are open drain and assert low when the voltage at their Applications respective adjust pins is below 88% (typ.) of nominal. If the voltage at the adjust pin is below 50% (typ.) of Notebook PCs nominal, the under voltage protection circuitry will shut Simple dual power supplies down that output. The SC338(A) is available in an MSOP-10 surface mount package. Typical Application Circuit 5V or 12V IN 1.2V +/-5% IN 1.8V +/-5% IN C1 C2 0.1uF (1) 0.1uF (1) 8 7 6 5 1 3 1.05V 3A 1.5V 1.5A Q1 C3 IRF7311 C4 or similar 2 4 100uF, 25mOhm POSCAP R1 100uF, 25mOhm POSCAP U1 SC338(A) R5 2k (2) R3 1 10 11.0k DRV1 IN R6 2k (2) 20.0k 2 9 ADJ1 DRV2 3 8 1.05V Enable EN1 ADJ2 4 7 1.05V Power Good 1.5V Enable PGD1 EN2 5 6 1.5V Power Good GND PGD2 R2 C5 C6 C7 R4 10.0k 10nF (2) 0.1uF 10nF (2) 10.0k R1 R3 Notes: V = 0.5 1+ V = 0.5 1+ OUT1 OUT2 (1) Additional capacitance may be required if far from supply R2 R4 (2) Optional soft-start components Revision: November 12, 2004 1 www.semtech.comSC338(A) POWER MANAGEMENT PRELIMINARY Absolute Maximum Ratings Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions for extended periods of time may affect device reliability. Plarameter SmymboMsaximu Unit IVnput Supply Voltage -V0.3 to +13.2 IN DVrive Pins -V0.3 to +8.0 DRV (1) AVdjust and Power Good Pins , V -0.3 to +5.5 V ADJ PGD EVnable Pins -0.3 to V V EN IN Thermal Impedance Junction to Ambient 1W13 C/ JA Thermal Impedance Junction to Case 4W2 C/ JC OTperating Ambient Temperature Range -C40 to +85 A OTperating Junction Temperature Range -C40 to +125 J STtorage Temperature Range -C65 to +150 STG LTead Temperature (Soldering) 10 Sec. 3C00 LEAD EVSD Rating (Human Body Model) 2Vk ESD Note: (1) Or V , if V = 5V. IN IN Electrical Characteristics (1) Unless specified: T = 25C, V = V = 5V 5%, V = 1.5V 5%, 0A I 3A. A IN EN PWR OUT Values in bold apply over full operating ambient temperature range. Plarameter SsymboTnest Condition Mpi Txy Msa Unit IN SVupply Voltage 42.5 13. V IN QIuiescent Current V=05V 50 700 A Q IN V=012V 60 900 A IN SItandby Current B1oth EN low 0. 1.0 A Q(OFF) Both EN low, V = 12V 15.0 IN Undervoltage Lockout SVtart Threshold Vr5ising 3V.7 UVLO IN HVysteresis Vf0alling 0V.5 HYST IN EN EVnable Input Threshold Output on 1.3 V IH V Output off 0.7 IL 2004 Semtech Corp. 2 www.semtech.com