LTC3713

· Very Low VIN(MIN): 1.5V
· True Current Mode Control
· 5V Drive for N-Channel MOSFETs Eliminates Auxillary 5V Supply
· No Sense Resistor Required
· Uses Standard 5V Logic-Level N-Channel MOSFETs
· Adjustable Current Limit
· Adjustable Frequency
· Switch t_ON(MIN) < 100ns
· 2% to 90% Duty Cycle at 200kHz
· 0.8V ±1% Reference
· Power Good Output Voltage Monitor
· Programmable Soft-Start
· Output Overvoltage Protection
· Optional Short-Circuit Shutdown Timer
· Small 24-Lead SSOP Package

· Telecom Card 3.3V, 2.5V, 1.8V Step-Down
· Bus Termination (DDR memory, SSTL)
· Synchronous Buck with General Purpose Boost
· Low V_IN Synchronous Boost

Input Supply Voltage (V_IN2) .......................10V to 0.3V
Boosted Topside Driver Supply Voltage
(BOOST) .................................................... 42V to 0.3V
V_IN1, I_ON, SW1, SENSE+ Voltages ............. 36V to 0.3V
RUN/SS, PGOOD Voltages ........................... 7V to 0.3V
FCB, V_ON, V_RNG Voltages .......... INTV_CC + 0.3V to 0.3V
I_TH, VF_B1, SENSE Voltages ................... 2.7V to 0.3V
SW2 Voltage ............................................ 36V to 0.4V
VFB2 Voltage .................................................V_IN2 + 0.3V
SHDN Voltage ........................................................... 10V
TG, BG, INTV_CC Peak Currents.................................... 2A
TG, BG, INTV_CC RMS Currents ................................ 50mA
Operating Ambient Temperature
Range (Note 4) .................................... 40°C to 85°C
Junction Temperature (Note 2) ............................ 125°C
Storage Temperature Range ...............65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C

The LTC^®3713 is a high current, high efficiency synchronous buck switching regulator controller optimized for use with very low input supply voltages. The LTC3713 operates from inputs as low as 1.5V and provides a regulated output voltage from 0.8V up to (0.9)V_IN. The controller uses a valley current control architecture to enable high operating frequencies without requiring a sense resistor. Operating frequency is selected by an external resistor and is compensated for variations in V_IN and V_OUT. The LTC3713 uses a pair of standard 5V logic-level N-channel external MOSFETs, eliminating the need for expensive P-channel or low threshold devices.

Discontinuous mode operation of LTC3713 provides high efficiency operation at light loads. A forced continuous control pin reduces noise and RF interference, and can assist secondary winding regulation by disabling discontinuous operation when the main output is lightly loaded. Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and an optional short-circuit shutdown timer.