By Torex Semiconductor, Ltd. 462
Torex Semiconductor's XC9248 series is an 18 V bootstrap, synchronous step-down DC/DC converter with built-in Nch-Nch driver transistors. Input voltage range from 4.5 V to 18 V and maximum output current is 2.2 A. The series is suitable for digital home appliance power supplies and works with small ceramic capacitors. The series also has a 0.8 V reference voltage. Using externally connected resistors, the output voltage can be set freely from 1.0 V to 12 V. The control method is synchronous PWM (source/ sink). The soft start time is internally set to 2.8 ms (typ), but can be adjusted using external capacitor. With UVLO (under voltage lock out) function, the internal driver transistors are forced off when input voltage falls down below 3.8 V (typ). The series includes over current protection, VOUT short-circuit protection, Lx short-circuit protection, VOUT overvoltage protection and thermal shutdown.