By Torex Semiconductor, Ltd. 26
The Torex Semiconductor XC9140 series are step-up synchronous DC/DC converters that support ceramic capacitors and have an internal 0.6 Ω (typ.) Nch driver transistor and an internal 0.65 Ω (typ.) Pch synchronous rectifier switch transistor. PFM control enables a low quiescent current, making these products ideal for portable devices that require high efficiency.
When the output voltage is 3.3 V and the load current is 1 mA, startup from an input voltage of VIN=0.9 V is possible. This means that the XC9140 can start from a single alkaline or nickel-metal-hydride battery. The output voltage can be set from 1.8 V to 5.0 V (±2.0%) in steps of 0.1 V.
The XC9140 features a load disconnect function to break continuity between the input and output at shutdown (XC9140A). It also includes a bypass mode function to maintain continuity between the input and output (XC9140C).
A version with a UVLO (Under Voltage Lock-Out) function will also be available (currently under development) which enables the prevention of battery leakage by stopping the IC's operation when the input voltage is low. The standard product will have a UVLO release voltage, of 2.15 V (±3.0%) and a custom version with a UVLO release voltage, selectable from between 1.65 V to 2.2 V in steps of 0.1 V, will be available.