Datasheet LTC3611 (Analog Devices)

LTC3611 10A, 32V Monolithic Synchronous Step-Down DC/DC Converter FeAtures Description n
10A Output Current
The LTC®3611 is a high efficiency, monolithic synchronous n
Wide VIN Range = 4.5V to 32V (36V Maximum)
step-down DC/DC converter that can deliver up to 10A n
Internal N-Channel MOSFETs
output current from a 4.5V to 32V (36V maximum) input n
True Current Mode Control
supply. It uses a constant on-time val ey current mode n
Optimized for High Step-Down Ratios
control architecture to deliver very low duty cycle opera- n
t0N(MIN) ≤ 100ns
tion at high frequency with excel ent transient response. n
Extremely Fast Transient Response
The operating frequency is selected by an external resistor n
Stable with Ceramic COUT
and is compensated for variations in VIN and VOUT. n
±1% 0.6V Voltage Reference
The LTC3611 can be configured for discontinuous or n Power Good Output Voltage Monitor forced continuous operation at light load. Forced continu- n Adjustable On-Time/Switching Frequency (>1MHz) ous operation reduces noise and RF interference while n Adjustable Current Limit discontinuous mode provides high efficiency by reducing n Programmable Soft-Start switching losses at light loads. n Output Overvoltage Protection n Optional Short-Circuit Shutdown Timer Fault protection is provided by internal foldback current n Low Shutdown I limiting, an output overvoltage comparator and an optional Q: 15μA n Available in a 9mm × 9mm 64-Pin QFN Package short-circuit shutdown timer. Soft-start capability for sup- ApplicAtions ply sequencing is accomplished using an external timing capacitor. The regulator current limit is user programmable. A power good output voltage monitor indicates when n Point of Load Regulation the output is in regulation. The LTC3611 is available in a n Distributed Power Systems compact 9mm × 9mm QFN package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Patents including 5481178, 6100678, 6580258, 5847554, 6304066. typicAl ApplicAtion
High Efficiency Step-Down Converter Efficiency and Power Loss vs Load Current
182k 0.1µF VOUT VON ION 100 10000 V V IN OUT = 2.5V RUN/SS VIN 4.5V TO 32V 90 10µF V 100pF 80 IN = 5V LTC3611 ×3 VIN = 25V 1000 POWER LOSS (mW) 1µH V 70 OUT SW 2.5V 60 680pF 10A 0.22µF 100µF 100 I 50 TH BOOST ×2 POWER LOSS, 12.5k 40 VIN = 5V EFFICIENCY (%) SGND INTVCC 30 30.1k 10 FCB 20 POWER LOSS, 39.2k V INTV V 4.7µF 10 IN = 25V CC RNG PGND PGOOD 0 1 11k 0.01 0.1 1 10 EXTVCC VFB LOAD CURRENT (A) 3611 TA01a 9.5k 3611 TA01b 3611fd Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration order information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts