LTC1530 High Power Synchronous Switching Regulator Controller FEATURES DESCRIPTIO n High Power Buck Converter from 5V or 3.3V Input The LTC 1530 is a high power synchronous switching n Adjustable Current Limit in S0-8 with regulator controller optimized for 5V to 1.3V-3.5V output Topside FET R Sensing applications. Its synchronous switching architecture drives DS(ON) n No External Sense Resistor Required two external N-channel MOSFET devices to provide high n Hiccup Mode Current Limit Protection efficiency. The LTC1530 contains a precision trimmed n Adjustable, Fixed 1.9V, 2.5V, 2.8V and 3.3V Output reference and feedback system that provides worst-case n All N-Channel MOSFET Synchronous Driver output voltage regulation of 2% over temperature, load n Excellent Output Regulation: 2% over Line, Load current and line voltage shifts. Current limit circuitry and Temperature Variations senses the output current through the on-resistance of n High Efficiency: Over 95% Possible the topside N-channel MOSFET, providing an adjustable n Fast Transient Response current limit without requiring an external low value sense n Fixed 300kHz Frequency Operation resistor. n Internal Soft-Start Circuit The LTC1530 includes a fixed frequency PWM oscillator n Quiescent Current: 1mA 45m A in Shutdown that free runs at 300kHz, providing greater than 90% efficiency in converter designs from 1A to 20A of output U current. Shutdown mode drops the LTC1530 supply cur- APPLICATIO S rent to 45m A. n Power Supply for Pentium II, AMD-K6 -2, SPARC, The LTC1530 is specified for commercial and industrial ALPHA and PA-RISC Microprocessors temperature ranges and is available in the S0-8 package. n High Power 5V to 1.3V-3.5V Regulators , LTC and LT are registered trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corp. AMD-K6 is a registered trademark of Advanced Micro Devices, Inc. TYPICAL APPLICATIO Efficiency vs Load Current V IN 5V 100 MBR0530T1 MBR0530T1 90 80 0.1F + C 1200F + IN 2.7k 70 4 10F 0.22F 60 50 L1 PV I G1 Q1 MAX CC 2H V 20 OUT 40 3.3V COMP I FB + C 14A 30 OUT LTC1530-3.3 150pF 10k 330F G2 Q2 20 7 1530 F01a V OUT GND 0.022F 10 T = 25C C : SANYO 10MV1200GX A IN C : AVX TPSE337M006R0100 0 OUT 0 2 4 6 8 10 12 14 L1: COILTRONICS CTX02-13198 0.3 OR PANASONIC ETQP6F2R5HA LOAD CURRENT (A) Q1, Q2: SILICONIX SUD50N03-10 1530 F01b Figure 1. Single 5V to 3.3V Supply 1530fa 1 EFFICIENCY (%) U ULTC1530 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) ORDER PART Supply Voltage NUMBER PV ........................................................................ 14V CC TOP VIEW Input Voltage LTC1530CS8 PV 1 8 G1 CC I (Note 2) ............................................... PV + 0.3V LTC1530CS8-1.9 FB CC GND 2 7 G2 I ........................................................ 0.3V to 14V LTC1530CS8-2.5 MAX *V / SENSE 3 6 I FB V OUT I Input Current (Notes 2,3) ............................ 100mA LTC1530CS8-2.8 FB COMP 4 5 I MAX Operating Ambient Temperature Range LTC1530CS8-3.3 S8 PACKAGE LTC1530C ............................................... 0 C to 70 C LTC1530IS8 8-LEAD PLASTIC SO LTC1530I............................................ 40 C to 85 C LTC1530IS8-1.9 T = 125 C, q = 130 C/ W JMAX JA Maximum Junction Temperature LTC1530IS8-2.5 *V FOR FIXED VOLTAGE VERSIONS OUT LTC1530C, LTC1530I ...................................... 125 C LTC1530IS8-2.8 Storage Temperature Range ................. 65 C to 150 C LTC1530IS8-3.3 Lead Temperature (Soldering, 10 sec).................. 300 C S8 PART MARKING 530I28 153028 1530I 1530 530I33 153019 153033 530I19 530I25 153025 Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The l denotes specifications that apply over the full operating temperature range, otherwise specifications are at T = 25 C. PV = 12V unless otherwise noted. (Note 3) A CC SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Internal Feedback Voltage LTC1530CS8 (Note 4) 1.223 1.235 1.247 V SENSE l 1.216 1.235 1.254 V V Output Voltage LTC1530CS8-1.9 (Note 4) 1.881 1.9 1.919 V OUT l 1.871 1.9 1.929 V LTC1530CS8-2.5 (Note 4) 2.475 2.5 2.525 V l 2.462 2.5 2.538 V LTC1530CS8-2.8 (Note 4) 2.772 2.8 2.828 V l 2.758 2.8 2.842 V LTC1530CS8-3.3 (Note 4) 3.267 3.3 3.333 V l 3.250 3.3 3.350 V g Error Amplifier Transconductance (Note 5) l 1.6 2 2.6 millimho mERR The l denotes specifications that apply over the full operating temperature range, otherwise specifications are at T = 25 C. A PV = 12V unless otherwise noted. (Note 3) CC SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS PV Supply Voltage (Note 6) l 13.2 V CC V Undervoltage Lockout Voltage (Note 7) 3.5 3.75 V UVLO V Internal Feedback Voltage LTC1530IS8 (Note 4) 1.223 1.235 1.247 V SENSE l 1.210 1.235 1.260 V 1530fa 2 U WWW