USP6C – XC9235, 36, 37

600mA Synchronous Step-Down DC/DC Converters

The XC9235 series is a group of synchronous-rectification type DC/DC converters with a built-in 0.42ΩP-ch MOS driver transistor and 0.52ΩN-ch MOS switching transistor, designed to allow the use of ceramic capacitors. Operating voltage range is from 2.0V to 6.0V (types A～C), 1.8V to 6.0V (types D～G). For the D/F types which have a reference voltage of 0.8V (±2.0%), the output voltage can be set from 0.9V by using two external resistors. The types A/B/C/E/G have a fixed output voltage from 0.8V to 4.0V in increments of 0.05V (±2.0%). The device provides a high efficiency, stable power supply with an output current of 600mA to be configured using only a coil and two capacitors connected externally. With the built-in oscillator, either 1.2MHz or 3MHz can be selected for suiting to your particular application.

The soft start and current control functions are internally optimized. During stand-by, all circuits are shutdown to reduce current consumption to as low as 1.0μA or less. The types B/F/G have a high speed soft-start as fast as 0.25ms in typical for quick turn-on. With the built-in UVLO (Under Voltage Lock Out) function, the internal P-channel MOS driver transistor is forced OFF when input voltage becomes 1.4V or lower.

The types B to G integrate CL discharge function which enables the electric charge at the output capacitor C_L to be discharged via the internal discharge switch located between the L_X and V_SS pins. When the devices enter stand-by mode, output voltage quickly returns to the V_SS level as a result of this function.

Three types of package SOT-25, USP-6C, and USP-6EL and WLP-5-03 are available.

Typical Application Circuit

Features