The TPS61291 is a boost converter with pin selectable output voltages and an integrated
bypass mode. In bypass operation, the device provides a direct path from the input to the system
and allows a low power micro controller (MCU) such as the MSP430 to operate directly from a single
3V Li-MnO2 battery or dual alkaline battery cells.
In bypass mode the integrated feedback divider network for boost mode
operation is disconnected from the output and the quiescent current consumption drops down to only
In boost mode the device provides a minimum output current of 200mA at
3.3V VOUT from 1.8V VIN. The boost mode is used for
system components which require a regulated supply voltage and cannot directly operate from the
input source. The boost converter is based on a current-mode controller using synchronous
rectification to obtain maximum efficiency and consumes typically 5.7µA from the output. During
startup of the boost converter, the VSEL pin is read out and the integrated feedback network sets
the output voltage to 2.5V, 3V or 3.3V.
Bypass mode or boost mode operation is controlled by the system via the
The device integrates an enhanced bypass mode control to prevent charge,
stored in the output capacitor during boost mode operation, from flowing back to the input and
charging the battery.
The device is packaged in a small 6-pin SON package (DRV) measuring 2.0mm
× 2.0mm × 0.75mm.