The converter can provide a 500mA output current from an input voltage ranging between 2.3V and 5.5V. It has a fixed output voltage of 1.82V. Efficiency at an input voltage of 3.6V and an output current of 150mA is 83%.
It runs at a 6MHz switching frequency, which means that it can operate with a tiny inductor that has a nominal value of just 470nH, and an output capacitor of only 4.7μF. The ST1S15 itself is housed in a Flip Chip 6 package measuring 1.2mm x 0.9mm.
This means that the total footprint of a buck converter circuit based on the ST1S15 is extremely small.
At the same time, the device’s high-frequency operation provides for very fast response to both load and line transients.
A pulse frequency mode can be selected to provide high efficiency under light-load conditions. In normal operation, the ST1S15 uses PWM mode for tight regulation and the best dynamic performance.
- 45μA quiescent current in PFM mode
- 10mV peak-to-peak output-voltage ripple in PWM mode
- Short-circuit protection
- Thermal-overload protection
- 130°C/W junction-to-ambient thermal resistance
- Core supply for DSP or multimedia processor
- Portable electronics devices
The STEVAL-ISA131V1 is an evaluation board for the ST1S15, providing 500mA of output current from an input voltage of 2.3V to 5.5V.
Orderable Part Number: STEVAL-ISA131V1