POWER LOSS (W) LT3434 High Voltage 3A, 200kHz Step-Down Switching Regulator with 100A Quiescent Current FEATURES DESCRIPTIO The LT 3434 is a 200kHz monolithic buck switching Wide Input Range: 3.3V to 60V regulator that accepts input voltages up to 60V. A high 3A Peak Switch Current efficiency 3A, 0.1 switch is included on the die along with Burst Mode Operation: 100A Quiescent Current** all the necessary oscillator, control and logic circuitry. Low Shutdown Current: I < 1A Q Current mode topology is used for fast transient response Power Good Flag with Programmable Threshold and good loop stability. Load Dump Protection to 60V 200kHz Switching Frequency Innovative design techniques integrated in a new high Saturating Switch Design: 0.1 voltage process achieve high efficiency over a wide input Peak Switch Current Maintained Over range. Efficiency is maintained over a wide output current Full Duty Cycle Range* range by employing Burst Mode operation at low currents, 1.25V Feedback Reference Voltage utilizing the output to bias the internal circuitry, and by Easily Synchronizable using a supply boost capacitor to fully saturate the power Soft-Start Capability switch. Patented circuitry maintains peak switch current Small 16-Pin Thermally Enhanced TSSOP Package over the full duty cycle range.* Shutdown reduces input U supply current to less than 1A. External synchronization APPLICATIO S can be implemented by driving the SYNC pin with logic-level inputs. A single capacitor from the C pin to the output High Voltage Power Conversion SS provides a controlled output voltage ramp (soft-start). The 14V and 42V Automotive Systems device also has a power good flag with a programmable Industrial Power Systems threshold and time-out, and thermal shutdown protection. Distributed Power Systems Battery-Powered Systems The LT3434 is available in a 16-pin TSSOP package with , LTC and LT are registered trademarks of Linear Technology Corporation. All other Exposed Pad leadframe for low thermal resistance. trademarks are the property of their respective owners. Burst Mode is a registered trademark of Linear Technology Corporation. *Protected by U.S. Patents including 6498466. **See Burst Mode Operation section for conditions. TYPICAL APPLICATIO Supply Current vs Efficiency and Power Loss 14V to 3.3V Step-Down Converter with Input Voltage vs Load Current 150 100A No Load Quiescent Current 100 10 V = 3.3V V = 12V OUT IN V = 5V OUT V OUT 125 EFFICIENCY V 3.3V V BOOST IN IN 75 1 4.7F 33H 0.68F 2A 4148 SHDN 100V 100 SW V = 3.3V OUT CER 0.1F LT3434 30MQ100 C SS 75 50 0.1 V C 4700pF 470pF V BIAS TYPICAL POWER 165k 50 27pF FB LOSS 10k 1% 100F 25 0.01 C T 6.3V PGFB 1F SYNC TANT 25 100k PG GND 1% 0 0 0.001 3434 TA01 0 10 20 30 40 50 60 0.0001 0.001 0.01 0.1 1 10 INPUT VOLTAGE (V) LOAD CURRENT (A) 3434 TA02a 3434 TA02b 3434fb 1 SUPPLY CURRENT (A) EFFICIENCY (%) U ULT3434 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW V , SHDN, BIAS, PGOOD, SW ............................... 60V IN ORDER PART BOOST Pin Above SW ............................................ 35V NC 1 16 PGOOD NUMBER BOOST Pin Voltage ................................................. 68V SW 2 15 SHDN LT3434EFE V 3 14 SYNC SYNC, C , PGFB, FB................................................ 6V IN SS LT3434IFE V 4 13 PGFB Operating JunctionTemperature Range IN 17 SW 5 12 FB LT3434EFE (Note 2) ........................ 40C to 125C BOOST 6 11 V C LT3434IFE (Note 2) ......................... 40C to 125C C 7 10 BIAS FE PART T Storage Temperature Range ................. 65C to 150C GND 8 9 C MARKING SS Lead Temperature (Soldering, 10 sec).................. 300C FE PACKAGE 3434EFE 16-LEAD PLASTIC TSSOP T = 125C, = 45C/W, = 10C/W 3434IFE JMAX JA JC(PAD) EXPOSED PAD IS GND (PIN 17) MUST BE SOLDERED TO GND (PIN 8) Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: