LT3791-1 60V 4-Switch Synchronous Buck-Boost Controller FeaTuresDescripTion n 4-Switch Single Inductor Architecture Allows VIN The LT®3791-1 is a synchronous 4-switch buck-boost volt- Above, Below or Equal to VOUT age/current regulator controller. The controller can regulate n Synchronous Switching: Up to 98.5% Efficiency output voltage, output current, or input current with input n Wide VIN Range: 4.7V to 60V voltages above, below, or equal to the output voltage. The n 2% Output Voltage Accuracy: 1.2V ≤ VOUT < 60V constant-frequency, current mode architecture allows its n 6% Output Current Accuracy: 0V ≤ VOUT < 60V frequency to be adjusted or synchronized from 200kHz n Input and Output Current Regulation with Current to 700kHz. No top FET refresh switching cycle is needed Monitor Outputs in buck or boost operation. With 60V input, 60V output n No Top FET Refresh in Buck or Boost capability and seamless transitions between operating n VOUT Disconnected from VIN During Shutdown regions, the LT3791-1 is ideal for voltage regulator, bat- n C/10 Charge Termination and Output Shorted Flags tery/super-capacitor charger applications in automotive, n Capable of 100W or greater per IC industrial, telecom, and even battery-powered systems. n 38-Lead TSSOP with Exposed Pad For new designs we recommend the LT8390: 60V synchro- nous 4-switch buck-boost controller due to its numerous applicaTions performance improvements over the LT3791-1. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Analog n Automotive, Telecom, Industrial Systems Devices, Inc. All other trademarks are the property of their respective owners. n High Power Battery-Powered System Typical applicaTion120W (24V 5A) Buck-Boost Voltage Regulator VIN 0.003Ω 12V TO 58V + 4.7µF 47µF VIN INTVCC 100V 80V 1µF 4.7µF 50Ω BST2 + IVINN 220µF 470nF 35V Efficiency vs Load Current IVINP 0.015Ω V BST1 0.1µF OUT 100 24V TEST1 499k 499k 4.7µF 5A TG1 0.1µF 50V 95 EN/UVLO ×2 SWI 73.2k 90 OVLO 10µH BG1 56.2k 27.4k INTVCC 85 3.83k LT3791-1 SNSP 100k 200k 80 SHORT 0.004Ω EFFICIENCY (%) 75 C/10 SNSN CCM PGND 70 IVINMON VIN = 12V BG2 65 ISMON VIN = 24V V CLKOUT SW2 IN = 54V 60 PWMOUT TG2 0 1 2 3 4 5 VREF ISP LOAD CURRENT (A) 0.1µF 37911 TA01b PWM ISN 100k CTRL SS SYNC V FB C RT SGND 37911 TA01a 5.1k 147k 33nF 200kHz 10nF 37911fb For more information www.linear.com/LT3791-1 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Typical Application Related Parts