Batteries and Portable Power

Dual-Output Boost Regulator Features 150nA Quiescent Current

Touchstone Semiconductor, Inc. today announced the TS3310 dual-output boost regulator. The TS3310 consumes only 150nA of supply current. Boost regulators are traditionally the highest current consumer in a system during sleep modes. The TS3310 removes this major constraint in power budgeting and enables years of battery life from a tiny battery cell. The TS3310 features an always-on output and an instant-on output. The always-on output is designed for powering a microcontroller, enabling long battery life by minimizing battery drain during sleep mode. The instant-on output is suited for powering a short-burst load, such as a Zigbee or Bluetooth radio.

"When designing the TS3310, it was our goal to build a boost regulator usable in long-life battery-powered or small energy-harvesting-powered systems. It features a quiescent current 20-times lower than competitive devices combined with a secondary output load switch to completely disconnect selected loads from the energy source," stated Martin Tomaz, a senior scientist at Touchstone Semiconductor.

The TS3310 operates from supply voltages as low as 0.9V up to 3.6V and can deliver at least 50mA of continuous output current. The TS3310 is suited to be powered from a wide variety of power sources including tiny button cells, single or multiple-cell alkaline cells or single Li-chemistry batteries. The boost regulator's output voltage range can be user-set from 1.8V to 5V to power a wide range of microcontrollers, low-power analog circuits and radio burst loads simultaneously. The TS3310 can also charge up a buffer capacitor to provide large burst currents to high power radios or other peripherals, even from tiny coin cell batteries. The TS3310 recharges the capacitor in a controlled fashion to prevent excessive current draw from the battery.

The TS3310 also addresses the problem of leaky peripherals. The instant-on output features a load switch that allows users to "pull the plug" on a peripheral that draws unwanted current when it should be off. For example, a radio peripheral that draws 10µA in the "off" mode still consumes more than 10X the current drawn by a sleeping microcontroller. Users can turn off the load switch to eliminate the battery drain.

The TS3310 has a fail-safe battery protection feature. If the battery voltage drops because of cold temperatures, or at the end of life, the battery's internal impedance goes up. An undervoltage lockout then scheme "pauses" the switching activity, so the battery cannot get dragged down below 900mV.

Operating from very low power sources, such as coin cells, AAAA cells or AAA cells, the TS3310 is designed for handheld/portable applications. This includes wireless remote sensors, RFID tags, wireless microphones, solar cell post-regulator/chargers, post-regulators for energy harvesting, blood glucose meters and personal health-monitoring devices.

The TS3310 is priced at $0.99 in 1K-piece quantities. The TS3310 is fully specified over the -40°C to +85°C temperature range and is available in a low-profile, thermally-enhanced 10-pin, 2mm x 2mm TDFN package.