What are the key needs of an Energy Harvesting (EH) power supply? Well, first of all, battery redundancy power needs to be available at times when the ambient power is not available. Of course, we want to extend battery life by harvesting ambient energy from thermal, vibration, solar, etc. To make the front end of our power supply more versatile, it would be useful to be able to convert both AC (piezo, magnetic, etc.) or DC (solar) energy transducers with a fairly wide voltage range and also to have an input prioritizer that could decide whether to use the energy harvesting input or the battery input.

A synchronous buck-boost would make a versatile power converter, and low quiescent current is a plus. Keeping the output regulated would be important when transitioning between ambient and battery power and vice-versa. A good, solid current output capability with possibility of different selectable output voltages would top off the wish list.

 

The LTC3330 does all of the above.

nano-power buck-boost DC-DC 01 TESLA-Institute

Linear Technology announced the LTC3330, a complete regulating energy harvesting solution that delivers up to 50mA of continuous output current to extend battery life when harvestable energy is available. The IC requires no supply current from the battery (Iq=0) when providing regulated power to the load from harvested energy and only 750 nA operating when powered from the battery under no-load conditions.

The regulator integrates a high voltage energy harvesting power supply, plus a synchronous buck-boost DC/DC converter powered by a primary cell battery to create a single non-interruptible output for energy harvesting applications such as those in wireless sensor networks.

nano-power buck-boost DC-DC 02 TESLA-Institute

A comprehensive block diagram shows the high level of integration in this power supply

The energy harvesting power supply, consisting of a full-wave bridge rectifier accommodating AC or DC inputs and a high efficiency buck converter, harvests energy from piezoelectric (AC), solar (DC) or magnetic (AC) sources. The primary cell input powers a buck-boost converter that operates from 1.8V to 5.5V at its input when harvested energy is not available to regulate the output whether the input is above, below or equal to the output. The IC automatically transitions to the battery when the harvesting source is no longer available.

 

nano-power buck-boost DC-DC 03 TESLA-Institute

A typical application diagram

 

The device’s energy harvesting inputs operate from a voltage range of 3V to 19V, AC or DC, making it ideal for a wide array of piezoelectric, solar or magnetic energy sources. Its input under-voltage lockout threshold settings are programmable between 3V and 18V, enabling the application to operate the energy harvesting source at its peak power transfer point. Other features include programmable DC/DC nd LDO output voltage post-regulator for powering a microcontroller, buck-boost peak current limits, super-capacitor charger/balancer and an input protective shunt (up to 25mA at VIN >20V).

 

nano-power buck-boost DC-DC 04 TESLA-Institute

 

 

 

 

Learn with TESLA

b small 1 TESLA INSTYTUTE

TESLA Project

b small 2 TESLA INSTYTUTE

TESLA Training Center

b small 3 TESLA INSTYTUTE

Sunday the 19th. Custom text here - TESLA INSTITUTE