TPS60311

The TPS6031X step-up, regulated charge pumps generate a 3-V ±4% or 3.3-V ±4% output voltage from a 0.9-V to 1.8-V input voltage (one alkaline, NiCd, or NiMH battery).

Only five small 1-uF ceramic capacitors are required to build a complete high-efficiency dc/dc charge pump converter. To achieve the high efficiency over a wide input voltage range, the charge pump automatically selects between a 3x or 4x conversion mode.

Output 1 (OUT1) can deliver a maximum of 40 mA, from a 1-V input, with output 2 (OUT2) not loaded. OUT2 can deliver a maximum of 20 mA, from a 1-V input, with OUT1 not loaded. Both outputs can be loaded at the same time, but the total output current of the first voltage doubler must not exceed 40 mA. For example, the load at OUT1 is 20 mA and the load at output 2 is 10 mA.

In snooze mode, the devices operate with a typical operating current of 2 uA, while the output voltage is maintained at 3.3 V ±10% or 3 V ±10%, respectively. This is lower than the self-discharge current of most batteries. Load current in snooze mode is limited to 2 mA. If the load current increases above 2 mA, the output voltage drops further and the devices automatically exits the snooze mode and operate in normal mode to regulate to the nominal output voltage with higher output currents. The device is set into the snooze mode by taking the SNOOZE\ pin low, and is set into normal operating mode by taking the SNOOZE\ pin high.

A power-good function supervises the output voltage of OUT2 and can be used for power up and power down sequencing. Power-good (PG) is offered as either open-drain or push-pull output.