LT8350 40V , 18V , 6A Synchronous IN OUT Buck-Boost Silent Switcher FEATURES DESCRIPTION n 4-Switch Single Inductor Architecture Allows V The LT 8350 is a monolithic 4-switch synchronous buck- IN Above, Below or Equal to V boost converter with Silent Switcher architecture to mini- OUT n Silent Switcher Architecture for Low EMI mize EMI emissions while delivering high efficiency at n Up to 95% Efficiency at 2MHz high switching frequency. The switcher can regulate the n Proprietary Peak Current Mode output voltage, input or output current from input volt- n 3V to 40V Input Voltage Range ages above, below, or equal to the output voltage. The n 1V to 18V Output Voltage Range proprietary peak current mode control scheme allows n 1.5% Output Voltage Regulation adjustable and synchronizable 200kHz to 2MHz fixed fre- n Output/Input Current Regulation and Monitor quency operation, or spread spectrum frequency modu- n Constant-Voltage/Constant-Current Regulation lation (SSFM) operation. With 3V to 40V input voltage n High Side PMOS Load Switch Driver range, 1V to 18V output voltage capability, and seam- n No Top MOSFET Refresh Noise in Buck or Boost less low noise transitions between operation regions, the n 200kHz to 2MHz Fixed Switching Frequency with LT8350 is ideal for voltage regulator, battery and super- External Frequency Synchronization and SSFM capacitor charger applications in automotive, industrial, n V Disconnected from V During Shutdown telecom, and battery powered systems. OUT IN n Small 4mm 6mm 32-Pin LQFN Package The LT8350 provides input or output current monitor and n AEC-Q100 Qualification in Progress power good flag. Robust fault protection is provided to detect output short-circuit condition, during which the APPLICATIONS LT8350 retries, latches off, or keepsrunning. n Automotive, Industrial, Telecom Systems All registered trademarks and trademarks are the property of their respective owners. n Voltage Regulator with Accurate Current Limit n High Frequency Battery-Powered System n USB-PD Source TYPICAL APPLICATION 95% Efficient 24W (12V, 2A) 2MHz Buck-Boost Voltage Regulator with Output Current Limit 100nF 100nF 2.2H Efficiency vs V IN 100 3.3A CURRENT LIMIT BST1 SW1 SW2 BST2 30m V IN 12V V V IN OUT 95 + 8V TO 36V 4.7F 4.7F 499k 110k 22F 10F EN/UVLO FB 90 115k 10k GND LT8350 RP 85 EXTV CC LOADEN 1F CLKOUT INTV CC 1F 80 V = 12V, f = 2MHz OUT SW ISP 100k I = 2A OUT ISN PGOOD I = 2.5A OUT 75 LOADTG V REF 0 5 10 15 20 25 30 35 40 ISMON CURRENT MONITOR INPUT VOLTAGE (V) CTRL 8350 TA01b 3.9k V C 220nF 3.3nF SS SYNC/MODE RT 8350 TA01a 22nF 14.3k 2MHz Rev. 0 1 Document Feedback For more information www.analog.com EFFICIENCY (%)LT8350 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V , EN/UVLO, ISP, ISN .............................. 0.3V to 42V IN V , EXTV ............................................ 0.3V to 20V OUT CC SW1 ........................................................... 0.3V to 42V 32 31 30 29 28 27 SW2 ........................................................... 0.3V to 20V BST1 .........................................................................47V V V 2 25 IN OUT BST2 .........................................................................25V V V 3 24 IN OUT 33 34 BST1SW1, BST2SW2, INTV ................. 0.3V to 5V CC GND GND CTRL, FB, LOADEN, SYNC/MODE, PGOOD .. 0.3V to 5V ISMON, V , RT ............................................. 0.3V to 5V C EN/UVLO 5 22 LOADTG SS, V ....................................................... 0.3V to 4V REF INTV 6 21 EXTV CC CC ISPISN ...........................................................1V to 1V CLKOUT, LOADTG .............................................. (Note 2) RP CLKOUT 7 20 35 36 Operating Junction Temperature Range (Notes 3, 4) GND GND LOADEN 8 19 SYNC/MODE LT8350R ............................................ 40C to 150C V 9 18 RT REF Storage Temperature Range .................. 65C to 150C SS ISMON 10 17 11 12 13 14 15 16 LQFN PACKAGE 32-LEAD (6mm 4mm 0.94mm) = 23C/W (DEMO BOARD EVAL-LT8350-AZ) JA EXPOSED PAD (PINS 33, 34, 35, 36) ARE GND, MUST BE SOLDERED TO PCB ORDER INFORMATION PART MARKING* PACKAGE MSL PART NUMBER PAD OR BALL FINISH DEVICE FINISH CODE TYPE** RATING TEMPERATURE RANGE LQFN (Laminate LT8350RV PBF Au (RoHS) 8350 e4 Package with 3 40C to 150C QFN Footprint) Contact the factory for parts specified with wider operating temperature LGA and BGA Package and Tray Drawings ranges. *Pad or ball finish code is per IPC/JEDEC J-STD-609. **The LT8350 package has the same footprint as a standard 4mm 6mm Recommended LGA and BGA PCB Assembly and Manufacturing QFN package. Procedures Rev. 0 2 For more information www.analog.com ISP SW1 ISN SW1 BST1 CTRL FB BST2 V SW2 C PGOOD SW2