LM27403 Synchronous Buck Controller

By Texas Instruments 91

LM27403 Synchronous Buck Controller

Texas Instruments' LM27403 is a feature-rich, easy-to-use, synchronous buck controller offering exceptional levels of integration and performance for superior efficiency in high power density, point-of-load (POL) DC-DC regulator solutions. The resistor-programmable switching frequency from 200 kHz to 1.2 MHz and integrated, high-current MOSFET gate drivers with adaptive deadtime offer flexibility to optimize solution size and maximize conversion efficiency. High precision and low output voltage are easily obtained with a 0.6 V, 1% accurate voltage reference together with a 30 ns high-side MOSFET minimum controllable on-time. Using lossless inductor DC resistance (DCR) current sensing and an inexpensive 2N3904 BJT to sense temperature remotely at the inductor, the LM27403 supports accurate and thermally-compensated overcurrent protection (OCP).

WEBENCH® LM27403 circuit design and simulation

  • Up to 97% efficiency and 93% duty cycle
  • Wide input voltage range of 3 V to 20 V
  • Switching frequency from 200 kHz to 1.2 MHz
  • Inductor-DCR-based overcurrent protection with thermal compensation
  • 0.6 V reference with 1% feedback accuracy
  • 30 ns minimum on-time for low VOUT
  • Integrated high-current MOSFET drivers
    • Adaptive deadtime control
  • Ultrafast line and load transient response
    • High GBW error amplifier
    • PWM line feedforward