PMU Harvests Energy from 16 microWatts to 600 milliWatts
During last weeks' electronica 2016, Analog Devices introduced the ADP5091/ADP5092, an intelligent integrated energy harvesting nano-powered management solution that converts dc power from PV cells or thermoelectric generators (TEGs). The device charges storage elements such as rechargeable Li-Ion batteries, thin film batteries, super capacitors, or conventional capacitors, and powers up small electronic devices and battery-free systems.
The ADP5091/ADP5092 provides efficient conversion of the harvested limited power from a 16μW to 600mW range with sub-μW operation losses. With the internal cold-start circuit, the regulator can start operating at an input voltage as low as 380mV. After cold startup, the regulator is functional at an input voltage range of 80mV to 3.3V. An additional 150mA regulated output can be programmed by an external resistor divide or VID pin.
By sensing the input voltage, the control loop keeps the input voltage ripple in a fixed range to maintain stable dc-to-dc boost conversion. The OCV dynamic sensing mode and none-sensing mode both programming regulation points of the input voltage allow extraction of the highest possible energy from the harvester. A programmable minimum operation threshold (MINOP) enables boost shutdown during a low light condition. As a low light indicator for microprocessor, the LLD is the MIONP comparator output. In addition, the DIS_SW pin can temporarily shut down the boost regulator and is RF transmission friendly.
The charging control function of ADP5091/ADP5092 protects rechargeable energy storage, which is achieved by monitoring the battery voltage with programmable charging termination voltage and shutdown discharging voltage. In addition, a programmable PGOOD flag with programmable hysteresis monitors the SYS voltage.
An optional primary cell battery can be connected and managed by an integrated power path management control block that is programmable to switch the power source from the energy harvester, rechargeable battery, and primary cell battery.
The ADP5091/ADP5092 will be available in a 24-lead LFCSP and is rated for a −40 to +125 degrees C junction temperature range. Applications are expected to include: Photovoltaic (PV) cell energy harvesting; TEG energy harvesting; Industrial monitoring; Self-powered wireless sensor devices; and Portable and wearable devices with energy harvesting.
