Linear Technology today announced the H- and MP- grade versions of the LTC3851A, a wide input voltage range (4V to 38V) synchronous step-down DC/DC controller. Onboard MOSFET gate drivers enable the use of high power external MOSFETs to produce output currents up to 25A with output voltages ranging from 0.8V to 5.5V, suitable for point-of-load requirements. These H- and MP-grade versions are guaranteed to operating junction temperature ranges from -40°C to 150°C and -55°C to 150°C, respectively. Applications include automotive systems, industrial, medical, datacom and telecom.
A constant-frequency, current-mode architecture allows a selectable fixed or phase-locked loop (PLL) frequency from 250kHz to 750kHz. Output current sensing is accomplished by measuring the voltage drop across the output inductor (DCR) or using an optional sense resistor. Current foldback limits MOSFET heat dissipation during short circuit and overload conditions. Selectable continuous, pulse skipping or Burst Mode operation is user controlled to optimize light load efficiency.