Boost converter for battery-powered rails
The TPS61281YFFT is a synchronous step-up converter from Texas Instruments designed to generate a regulated output from a single Li-ion cell or two alkaline cells, with an input range of 2.3 V to 4.85 V. Its 3 A switch current rating and 2.3 MHz switching frequency allow it to deliver useful output current while keeping the external inductor small — typically 1 µH to 2.2 µH. The output is programmable via external resistors from a minimum of 2.85 V up to 4.4 V, making it a fit for 3.3 V or 5 V rails in portable instruments, wireless modules, and battery-backed sensors.
Switching frequency and inductor selection
At 2.3 MHz the converter operates above the AM broadcast band, reducing the risk of noise coupling into sensitive RF front-ends, and the high frequency shrinks the inductor footprint to a 2x2.5 mm or smaller component.
Package and PCB layout considerations
The 16-DSBGA package measures 1.67 mm x 1.67 mm with a 0.4 mm ball pitch — a 4-layer PCB is recommended to route the power and feedback traces out from under the BGA without vias blocking the thermal pad.