Datasheet LTC3613 (Analog Devices)

LTC3613 24V, 15A Monolithic Step Down Regulator with Differential Output Sensing
FEATURES DESCRIPTION
n
Wide VIN Range: 4.5V to 24V;
The LTC®3613 is a monolithic synchronous step-down
VOUT Range: 0.6V to 5.5V at up to 15A
switching regulator capable of regulating outputs from 0.6V n
0.67% Output Voltage Accuracy
to 5.5V with up to 15A output current. The controlled on-time n
Controlled On-Time Valley Current Mode Architecture,
constant frequency valley current mode architecture allows for
Excellent Current Sharing Capability
both fast transient response and constant frequency switch- n
Frequency Programmable from 200kHz to 1MHz
ing in steady-state operation, independent of VIN, VOUT and
and Synchronizable to External Clock
load. This also provides excellent current sharing capability. n
RSENSE or Inductor DCR Current Sensing With
Differential output voltage sensing along with a precision
Accurate Current Limit
internal reference combine to offer ±0.67% output regula- n Fast Transient Response tion, even if the output ground reference deviates from n Differential Output Voltage Sensing Allowing

500mV local ground by 500mV. The switching frequency can be Common Mode Remote Ground programmed from 200kHz to 1MHz with an external resis- n tON(MIN) = 65ns; tOFF(MIN) = 105ns tor. The switching frequency is also phase synchronizable n Overvoltage Protection and Current Limit Foldback to an external clock in applications where switching noise/ n Power Good Output Voltage Monitor EMI reduction is crucial. n Voltage Tracking Start-Up n External V Very low t CC Input for Bypassing Internal LDO ON and tOFF times allow for near 0% and near 100% n Micropower Shutdown: I duty cycles, respectively. Voltage tracking soft start-up is Q = 15μA n 7mm × 9mm 56-pin QFN Package provided for tracking and sequencing applications. Safety fea- tures include output overvoltage protection, programmable
APPLICATIONS
current limit with foldback, and power good monitoring. n Distributed Power System L, LT, LTC, LTM, OPTI-LOOP, Linear Technology and the Linear logo are registered trademarks and Hot Swap and No RSENSE is a trademark of Linear Technology Corporation. All other n Point-of-Load Converters trademarks are the property of their respective owners. Protected by U.S. Patents including n 5481178, 5487554, 6580258, 6304066, 6476589, 6774611. Servers
TYPICAL APPLICATION Efficiency and Power Loss High Efficiency High Power Step-Down Converter vs Load Current
INTVCC PVIN 100 3.5 V SV IN IN + 4.5V TO 24V 90 PULSE-SKIPPING MODE 0.1μF 82μF 3.0 80 100k LTC3613 PGOOD VOUT 70 2.5 POWER LOSS (W) 10Ω SENSE– 60 RUN 1000pF 10Ω 2.0 FORCED 50 V SENSE+ CONTINUOUS RNG 0.47μH 1.5mΩ VOUT MODE 1.5 MODE/PLLIN 40 SW 1.5V 0.1μF EFFICIENCY (%) EXTV 0.1μF 15A CC 15k 30 1.0 TRACK/SS BOOST 20 47pF 0.5 V 10k 10 IN = 12V INTV V CC OUT = 1.5V 270pF + 0 0 4.7μF 330μF 21k 0.01 0.1 1 10 PGND ×2 ITH LOAD CURRENT (A) 115k RT V + 3613 TA01a OSNS SGND V – OSNS 3613 TA01 3613fa 1