LT8616 Dual 42V Synchronous Monolithic Step-Down Regulator with 6.5A Quiescent Current FEATURES DESCRIPTION n Wide Input Voltage Range: 3.4V to 42V The LT 8616 is a high efficiency, high speed, dual synchro- n 2.5A and 1.5A Buck Regulators with Separate Inputs nous monolithic step-down switching regulator that con- n Fast Minimum Switch On-Time: 35ns sumes only 6.5A of quiescent current with both channels n Ultralow Quiescent Current Burst Mode Operation: enabled. Both channels contain all switches and necessary n 6.5A I Regulating 12V to 5V and 3.3V circuitry to minimize the need for external components. Q IN OUT OUT n Output Ripple < 15mV Low ripple Burst Mode operation enables high efficiency n 180 Out of Phase Switching down to very low output currents while minimizing output n Adjustable: 200kHz to 3MHz ripple. A SYNC pin allows synchronization to an external n Synchronizable: 250kHz to 3MHz clock. Internal compensation with peak current mode n Accurate 1V Enable Pin Thresholds topology allows the use of small inductors and results in n Internal Compensation fast transient response and good loop stability. The en- n Output Soft-Start and Tracking able pins have accurate 1V thresholds and can be used to n TSSOP Package: Output Stays at or Below Regulation program undervoltage lockout. Capacitors on the TR/SS Voltage During Adjacent Pin Short or When a Pin Is pins programs the output voltage ramp rate during start- Left Floating up while the PG pins signal when each output is within n Thermally Enhanced 28-Lead TSSOP and 10% of the programmed output voltage. The LT8616 is 3mm 6mm QFN Packages available in a TSSOP package for high reliability. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks APPLICATIONS of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Automotive and Industrial Supplies n General Purpose Step-Down TYPICAL APPLICATION 5V, 3.3V, 700kHz Step-Down Converter Efficiency 100 V IN V BOOST1 IN1 12V 0.1F 4.7F 90 EN/UV1 10H V OUT1 V = V = 12V SW1 IN1 IN2 80 V 5V, 1.5A IN2 f = 700kHz SW 1M 4.7F 5.6pF 47F EN/UV2 70 FB1 187k LT8616 60 PG1 1M PG2 50 BIAS SYNC/MODE 10nF BOOST2 40 CH1, 5V OUT 0.1F TR/SS1 CH2, 3.3V OUT 1F TR/SS2 4.7H 30 V OUT2 0.01 0.1 1 10 100 1000 INTV SW2 CC 3.3V, 2.5A LOAD (mA) 1M 10pF 56.2k 8616 TA01b RT FB2 GND 316k 2 x 47F 8616 TA01a 8616fa 1 For more information www.linear.com/LT8616 EFFICIENCY (%)LT8616 ABSOLUTE MAXIMUM RATINGS (Note 1) V , V , EN/UV1, EN/UV2, PG1, PG2 .....................42V Operating Junction Temperature Range (Note 2) IN1 IN2 BIAS ..........................................................................30V LT8616E ............................................. 40C to 125C BST1 Above SW1, BST2 Above SW2, FB1, FB2, LT8616I .............................................. 40C to 125C TR/SS1, TR/SS2 .....................................................4V LT8616H ............................................ 40C to 150C SYNC/MODE ...............................................................6V Storage Temperature Range .................. 60C to 150C PIN CONFIGURATION TOP VIEW TOP VIEW 1 TR/SS2 EN/UV2 28 2 FB2 PG2 27 28 27 26 25 3 FB2 SW2 26 NC 1 24 GND 4 NC SW2 25 SW2 2 23 GND 5 V SW2 24 IN2 SW2 3 22 GND 6 NC BOOST2 23 SW2 4 21 V IN2 7 BIAS NC 22 BOOST2 5 20 BIAS 29 29 GND GND 8 INTV BOOST1 6 19 INTV BOOST1 21 CC CC SW1 7 18 9 NC V SW1 20 IN1 8 SW1 17 GND 10 V SW1 19 IN1 NC 9 16 GND 11 NC PG1 18 PG1 10 15 SYNC/MODE 12 SYNC/MODE TR/SS1 17 11 12 13 14 13 EN/UV1 FB1 16 14 RT FB1 15 FE PACKAGE UDE PACKAGE 28-LEAD PLASTIC TSSOP 28-LEAD (3mm 6mm) PLASTIC QFN = 30C/W, = 10C/W JA JC(PAD) = 40C/W, = 5C/W JA JC(PAD) EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT8616EFE PBF LT8616EFE TRPBF LT8616FE 28-Lead Plastic TSSOP 40 to 125C LT8616IFE PBF LT8616IFE TRPBF LT8616FE 28-Lead Plastic TSSOP 40 to 125C LT8616HFE PBF LT8616HFE TRPBF LT8616FE 28-Lead Plastic TSSOP 40 to 150C LT8616EUDE PBF LT8616EUDE TRPBF LGMM 28-Lead 3mm 6mm Plastic QFN 40 to 125C LT8616IUDE PBF LT8616IUDE TRPBF LGMM 40 to 125C 28-Lead 3mm 6mm Plastic QFN Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: