LTC3834 30µA IQ Synchronous Step-Down Controller FEATURESDESCRIPTION n Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 10V The LTC®3834 is a high performance step-down switching n Low Operating Quiescent Current: 30µA regulator controller that drives an all N-channel synchro- n OPTI-LOOP® Compensation Minimizes COUT nous power MOSFET stage. A constant-frequency current n ± 1% Output Voltage Accuracy mode architecture allows a phase-lockable frequency of n Wide VIN Range: 4V to 36V up to 650kHz. n Phase-Lockable Fixed Frequency 140kHz to 650kHz The 30µA no-load quiescent current extends operating n Dual N-Channel MOSFET Synchronous Drive life in battery powered systems. OPTI-LOOP compensa- n Very Low Dropout Operation: 99% Duty Cycle tion allows the transient response to be optimized over n Adjustable Output Voltage Soft-Start or Tracking a wide range of output capacitance and ESR values. The n Output Current Foldback Limiting LTC3834 features a precision 0.8V reference and a power n Power Good Output Voltage Monitor good output indicator. The 4V to 36V input supply range n Clock Output for PolyPhase® Applications encompasses a wide range of battery chemistries. n Output Overvoltage Protection n Low Shutdown IQ: 4µA The TRACK/SS pin ramps the output voltage during n Internal LDO Powers Gate Drive from VIN or VOUT start-up. Current foldback limits MOSFET heat dissipation n Selectable Continuous, Pulse Skipping or during short-circuit conditions. A reduced feature set Burst Mode® Operation at Light Loads version of the part (LTC3834-1) is available in a smaller, n Small 20-Lead TSSOP or 4mm × 5mm QFN Package lower pin count package. Comparison of LTC3834 and LTC3834-1APPLICATIONSCLKOUT/PART #PHASMDEXTVCCPGOODPACKAGES LTC3834 Yes Yes Yes FE20/4mm × 5mm QFN n Automotive Systems LTC3834-1 No No No GN16/3mm × 5mm DFN n Telecom Systems n Battery-Operated Digital Devices L, LT, LTC, LTM, Burst Mode, PolyPhase and OPTI-LOOP are registered trademarks and No RSENSE is a trademark of Linear Technology Corporation. All other trademarks are the n Distributed DC Power Systems property of their respective owners. Protected by U.S. Patents, including 5408150, 5481178, 5705919, 5929620, 6304066, 6498466, 6580258, 6611131. TYPICAL APPLICATIONHigh Efficiency Synchronous Step-Down Converter VIN CLKOUT VIN 4V TO 36V PLLLPF 10µF 100 10000 RUN TG 90 0.01µF PGOOD 0.22µF 80 1000 TRACK/SS BOOST POWER LOSS (mW) 3.3µH 0.012Ω V 70 I OUT TH 560pF SW 3.3V LTC3834 60 100 5A 150pF 50 54.2k 150µF 40 10 SGND INTVCC EFFICIENCY (%) 30 68.1k PLLIN/MODE EXTV 4.7µF CC 20 1 VFB BG 10 SENSE– 215k 0 0.1 0.000001 0.0001 0.01 1 SENSE+ PGND OUTPUT CURRENT (A) 3834 TA01b 3834 TA01 3834fc For more information www.linear.com/LTC3834 1 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Operation Package Description Typical Application Related Parts
