A switching regulator coupled with an LDO in the same package is a very versatile component. Touchstone, with its first analog power management product, has enhanced such a function with the capability to use supply voltages down to 0.6V while still being able to deliver a 75 mA output current.
The device can be used in power harvesting or peak load buffering applications, the LDO may post-regulate voltage buffered in a large capacitor or super-capacitor at boost’s output. Finally, the LDO may be operated simply as an on/off load switch.
The TS3300 uses 3.5µA of supply current, and the device’s efficiency performance is constant over a 100:1 span in output current.
The IC is suited to be powered from a wide variety of power sources including single or multiple-cell alkaline or single Li-chemistry batteries. The boost regulator’s output voltage range can be user-set from 1.8V to 5.25V to power an entire range of low-power analog circuits, microcontrollers and low-energy Bluetooth™ radios simultaneously. While configured to produce a 3V output from a 1.2V input source, the IC’s efficiency performance is constant over a 100:1 span in output current. For powering low-energy radios, its internal, low-dropout linear regulator can deliver up to 100mA output current while reducing boost-converter-generated output voltage ripple by 3x.
Drawing only 3.5µA no-load supply current, the device is ideal for “always on” and other battery-powered or portable applications where extended battery run-time is a major system requirement. When used in systems where the primary power source is non-ideal or when the power source is weak, the IC includes an anti-crush feature that prevents the boost converter’s input voltage from excessive voltage drops; this, in turn, prevents the power source’s voltage from degrading beyond usefulness.
For more detail: Touchstone Semiconductor TS3300 ultra low-power, load independent, high-efficiency boost