SC2602/SC2602A Synchronous Voltage Mode Controller for Distributed Power Supply Applications POWER MANAGEMENT Features Description The SC2602 and SC2602A are low-cost, full featured, Synchronous operation for high efficiency (95%) synchronous voltage-mode controllers designed for use R current sensing DS(ON) in single ended power supply applications where efficiency On-chip power good and OVP functions is of primary concern. Synchronous operation allows for Small size with minimum external components the elimination of heat sinks in many applications. The Soft Start SC2602s are ideal for implementing DC/DC converters Enable function needed to power advanced microprocessors in low cost systems, or in distributed power applications where effi- ciency is important. Internal level-shift, high-side drive Applications circuitry, and preset shoot-thru control, allows the use of Microprocessor core supply inexpensive N-channel power switches. Low cost synchronous applications Voltage Regulator Modules (VRM) SC2602s features include temperature compensated DDR termination supplies voltage reference, triangle wave oscillator and current Networking power supplies sense comparator circuitry. Power good signaling, shut- Sequenced power supplies down, and over voltage protection are also provided. The SC2602 operates at a fixed 200kHz and the SC2602A at 500kHz, providing a choice for optimum compromise between efficiency, external component size, and cost. Two SC2602s can be used together to sequence power up of telecom systems. The power good of the first SC2602 connected to the enable of the second SC2602 makes this possible. Typical Application Circuit Typical Distributed Power Supply +5V + R4 C5 C6 C7 C8 Vin R1 R2 10 U1 C1 10.0 680/6.3V 680/6.3V 680/6.3V 1k SC2602 0.1 C2 0.1 5V 1 14 VCC GND PWRGD C3 0.1 2 13 PWRGD SS/SHDN SHDN 820pF R3 4.99K 0.1 1k 3 12 OVP OVP COMP R8 124* 4 11 OCSET SENSE R7 127 5 10 PHASE BSTH +12V C4 D1 1.0 Q1 L1 MBR0520 6 9 STP40NE 2uH DRVH BSTL + R5 Q2 3.9 STP40NE 7 8 PGND DRVL C9 C10 C11 C12 C13 180/4V 180/4V 180/4V 180/4V 180/4V Vout=2.5V R6 2.2 * NOTE: Figure 1. *) Vout = 1.265 x (1+R8/R7) 1 Revision: November 18, 2004 www.semtech.comSC2602/SC2602A POWER MANAGEMENT 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 Smymbo Msaximu Unit VVCC, BSTL to GND -V1.0 to 16 (20V Surge) IN PGND to GND V0.5 (1) PHASE to GND -V0.5 to 18 (20V Surge) BSTH to PHASE 1V6 (20V Surge) Thermal Resistance Junction to Case 4W5 C/ JC Thermal Resistance Junction to Ambient 1W15 C/ JA OTperating Temperature Range -C40 to +85 A MTaximum Junction Temperature 1C25 J STtorage Temperature Range -C65 to +150 STG LTead Temperature (Soldering) 10 Sec. 3C00 LEAD EDSD Rating (Human Body Model) E2S kV Note: (1) -1.5V to 20V for 25ns repetitive every cycle. Electrical Characteristics o Unless specified: V = 4.75V to 12.6V GND = PGND = 0V FB = V V = 12V V = 12V T = 25 C CC O BSTL BSTH-PHASE J Psarameter Cnondition Mpi Txy Msa Unit Power Supply SCupply Voltage V2C 46. 1V2. SCupply Current E6N = VC 1A0 m LVine Regulation V5O = 2.5 0%. Error Amplifier Tmransconductance G81S. m Gain (AOL) 5B0 d Input Bias 58 A Oscillator O2scillator Frequency S0C260 108 200 2z2 kH S0C2602A 405 500 55 O0scillator Max Duty Cycle 959% Internal Ramp Peak to Peak 1V MOSFET Drivers D,H Source/Sink BSTH - DH = 4.5V1A DH- PHASE = 2V D.L Source/Sink BSTL - DL = 4.5V1A DL - PGND. = 2V www.semtech.com 2004 Semtech Corp. 2