This requires only a single external resistor to regulate its output voltage making it extremely easy to use. However, most shunt references are actually based on a bandgap reference voltage. They can become unstable if charged over 100mV beyond their recommended float voltage.Ī shunt reference is a current-fed, two terminal device that draws no current until the target voltage is reached and is used like a Zener diode and is often shown on a circuit schematic as a Zener diode. Lithium-Ion/Polymer chemistry batteries provide the high performance features necessary for portable electronic devices but must be treated with care. A unique IC with sub-1uA quiescent operating current is necessary to charge a battery from this type of energy source. However, intermittent energy harvesting sources such as indoor photovoltaic arrays or piezoelectric transducers provide bursts of power. Typical battery charger ICs require a constant DC input voltage and cannot handle bursts of energy. Moreover, the ability to accurately and safely charge a Lithium-Ion/Polymer, coin cell or a thin film battery from a low-current source or an intermittent harvested energy source has been difficult to attain safely.ĭesign Challenges for Low Power Consumption Chargers To configure one to do such a task is extremely cumbersome. However, they cannot effectively charge a battery. Shunt voltage references are simple to use they have been around for many years and are in a myriad of products. And, so many implementations will want to charge a battery for a backup power source. Many energy harvesting applications inherently have intermittent or low-power sources. Recent technology developments have pushed energy harvesting to the point of commercial viability. Energy harvesting ICs can convert an appropriate transducer's output into an electric current for a battery charger device.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |