LM2743

· MOSFET input voltage (V_IN) from 1V to 16V (Note 2)
· IC input voltage (V_CC) from 3V to 6V
· Output voltage adjustable down to 0.6V
· Output over-voltage and under-voltage flag
· FB voltage: 2% over temperature
· Current limit without series sense resistor
· Adjustable soft start
· Tracking and sequencing with shutdown and soft start pins
· Switching frequency from 50 kHz to 2 MHz
· TSSOP-14 package

If Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.
VCC ..........................................................7V
BOOT Voltage .........................................21V
All other pins ...............................V_CC + 0.3V
Junction Temperature .......................150°C
Storage Temperature .......−65°C to 150°C
Soldering Information
Lead Temperature
(soldering, 10sec) .............................260°C
Infrared or Convection (20sec) .........235°C
ESD Rating (Note 3) ..............................2 kV

The LM2743 is a high-speed, N-Channel synchronous buck regulator controller with a 2%, 0.6V feedback reference voltage intended to make down conversion from 3.3V to as low as 0.6V easy. A fixed-frequency voltage-mode PWM control architecture is used, that is adjustable from 50kHz to 2MHz through an external resistor. This wide range of PWM frequencies gives the power supply designer the flexibility to make tradeoffs among component size, cost, noise and efficiency. The power MOSFETs can run on a separate 1V to 16V (Input Voltage, V_IN) (Note 2) rail while the regulator is biased from a 3V to 6V (IC Input Voltage, V_CC), 2mA rail. A power-good flag, precision shutdown threshold and soft start features make power supply tracking and sequencing easy.

The LM2743 employs output under-voltage and over-voltage flag, and current limit. Current limit is achieved by monitoring the voltage drop across the on resistance of the low-side MOSFET. The adaptive non-overlapping MOSFET gate drivers help avoid potential shoot-through problems while maintaining high efficiency. Both high-side and low-side MOSFETs are the lower cost N-Channel type, and the IC can accept a bootstrap structure to saturate the high-side MOSFET for highest efficiency.