500 mA buck — the load budget and inductor choice
The TPS62101DG4 is a 500 mA step-down (buck) switching regulator from Texas Instruments, built around a 600 kHz fixed switching frequency. The 500 mA ceiling sets the continuous load it can source — enough for a sensor rail, a small FPGA core, or a downstream LDO input, but not for a multi-amp motor drive or a high-current processor supply. The 600 kHz switching rate lets the designer use a physically smaller inductor than a 100 kHz part would need, at the cost of slightly higher switching losses. For a 500 mA rail, a 10 µH to 22 µH shielded inductor in a 4x4 mm package is typical; the exact value depends on the input-to-output voltage ratio and the ripple current target.
Output voltage range — adjustable down to 0.8 V
The 0.8 V floor is low enough to feed 1.2 V and 0.9 V core rails for modern FPGAs and SoCs, which older regulators with a 1.25 V minimum cannot reach. The 8 V maximum limits the output to rails below the 9 V input ceiling. This simplifies the BOM and improves efficiency at light loads, though the 500 mA output keeps the die temperature in check even without a heatsink in the 8-SOIC package.