Complete low BoM PMIC with dual energy harvesting source inputs
Date: 08/09/2023
The new energy harvesting IC AEM13920 from e-peas can handle simultaneous inputs from two independent harvested energy sources such as PV, RF, thermal and kinetic energy sources.
For the usage of energy harvesting in small electronics devices like remote controls, PC peripherals, wireless sensors, and more, the flexible dual-source capability enables new design opportunities.
Examples include: A remote control could have separate PV cells on its front and rear, to maintain an energy input whether the device is left face up or face down. A smart wireless light switch could operate on mechanical energy for short RF transmissions, and on stored mechanical or light energy for longer operations such as downloading and installing a firmware update.
AEM13920 provides a complete power management solution with added new features for system optimization and protection.
More than 90% source-to-storage and storage-to-load conversion efficiencies are achieved by the PMIC. The quantity of energy extracted from each type of harvester is maximized by using separate maximum power point tracking (MPPT) algorithms for each source and an extremely low cold-start input condition of 275 mV/5 W. Constant source-voltage regulation is another option available with the AEM13920.
Since AEM13920 implements all the functionalities necessary to store and utilise energy from an external harvester in a single chip eases power-system design and reduces component count and bill-of-materials cost. The supply to the storage element is controlled by two separate on-chip boost converters that convert the source voltage. The output from the storage element is changed to a fixed voltage between 0.6 V and 2.5 V needed by the application using a different on-chip buck regulator. In the event of a protracted period of operation without an input from an energy harvester, the AEM13920 also controls a 5 V power input that can be utilized to charge the storage element.
New control and configuration features introduced in the AEM13920 include:
Average Power Monitoring a circuit which measures total energy transferred from each of the two sources to storage, and total energy supplied to the load. This enables the host microcontroller to calculate the state of charge of the storage element, and to monitor system operation in detail.
I2C interface for control of 33 register settings by the host MCU, and for system data read-outs
The AEM13920 also offers a full suite of system monitoring and protection features, including:
Thermal monitoring of the storage element
Selectable over-charge and over-discharge limits for protection of the storage element
Shipping mode to protect the storage element
The AEM13920 is compatible with a wide range of rechargeable battery and storage element types, including hybrid lithium capacitors, lithium-polymer, LiFP, and li-ceramic batteries.
Christian Ferrier, Chief Marketing Officer of e-peas, said: e-peas has been pioneering the technology of energy harvesting for years, and the AEM13920 is the latest product of our innovation a fully integrated PMIC that enables designers to use the combination of two energy sources that is exactly right for their application.
And because our technology is so efficient and effective, the AEM13920 should encourage more OEMs to stop relying on wasteful primary batteries, and so reduce the amount of electrical waste that goes to landfill.
The AEM13920 is supplied in a 40-pin QFN package with a board footprint of 5mm x 5mm. It is available for sampling now. For sample requests and for information about the 2AAEM13920J051 evaluation board, go to www.e-peas.com.
