e-peas – Highly-Efficient Regulated Dual-Output, Ambient Energy Manager for AC or TEG sources with optional primary battery
The AEM30940 is an integrated energy management subsystem that extracts DC power from a TEG, a piezo generator, a micro turbine generator or high frequency RF inputs. The AEM30940 harvests the available input current up to 125mA. It integrates an ultra-low-power boost converter to charge a storage element, such as a Li-Ion battery, a thin film battery or a super- or conventional capacitor. The boost converter operates with input voltages in a range from 50 mV to 5V. With its unique cold-start circuit, it can start operating with empty storage elements at an input voltage as low as 380mV and an input power of just 3 µW.
The low voltage supply typically drives a microcontroller at 1.2V or 1.8 V. The high voltage supply may typically drive a radio transceiver at a configurable voltage. Both are driven by highly efficient LDO (Low Drop-Out) regulators for low noise and high stability.
Configuration pins determine various operating modes by setting predefined conditions for the energy storage element (overcharge or overdischarge voltages), and by selecting the voltage of the high voltage supply. Moreover, special modes can be obtained at the expense of a few configuration resistors.
The chip integrates all the active elements for powering a typical wireless sensor. With only seven external components, integration is maximum, footprint and BOM are minimum, optimizing the time-to-market and the costs of WSN designs in all markets.
Five capacitors and two inductors as well as the matching network passive components are required, available respectively in the small 0402 and 0603 SMD formats.