e TM ADVANCED EPAD LINEAR DEVICES, INC. EH4295 MICROPOWER STEP UP LOW VOLTAGE BOOSTER MODULE GENERAL DESCRIPTION FEATURES The EH4295 Micropower Step Up Low Voltage Booster Module, Nominal input impedance of 950 VIN=0.25V part of the EH4200 Series of Micropower Step Up Low Voltage Small footprint and volume less than 1 cu. in. Boosters, is a self-powered voltage-booster module that converts Simple and easy to use - just connect a 2-wire input source a low DC voltage input to a higher AC or DC voltage output suitable and 2-wire output load for many low-power energy harvesting applications using photo- Ready-to-Use out of the box, no circuit design required diodes, thermoelectric or electromagnetic generators as the input Direct interface to ALD s EH300/EH301 series of Energy source. The EH4295 does not need a separate power supply to Harvesting Modules operate and it derives its power directly from the low input voltage A range of models suitable for a variety of energy gener source. The EH4200 Series draws input power levels starting at as ating sources low as 2W, which enables an on-board self-starting oscillator. Self-starting at both very low operating voltage and low operating current levels The EH4295 features nominal input impedance of 950, making Self-contained booster with all components on-board it suitable for many different energy generating sources. The Built-in on-board miniature transformer for high-efficiency EH4200 Series is part of a growing family of Micro-power Low energy conversion Voltage Booster Modules, Energy Harvesting Modules and En- Unique custom on-board EPAD MOSFET arrays ergy Harvesting Integrated Circuits. Optional user-installed full wave rectifier on board to produce DC voltages The EH4295 is designed primarily for driving loads such as the Compatible with a wide range of voltage sources and a ALD EH300/EH301 Series Energy Harvesting Modules. The AC wide range of source impedances outputs of the EH4295 are connected directly to the input terminals Adaptable for use with a broad range of applications of the EH300/EH301 Series Energy Harvesting Modules with a No calibration or setup required two-wire cable. They can also be used for trickle-charge applica- Maintenance free operation tions such as battery charger or super-cap charger, including Long operating life situations where the energy input is not well controlled or regu- Virtually unlimited operating cycles lated. For certain applications, the EH4295 can also be used Moisture and dust protection without the EH300/EH301 Series Energy Harvesting Modules. RoHS compliant The EH4295 self-starting oscillator oscillates at a natural fre- APPLICATIONS quency of about 400Hz, which depends on the source impedance, the source voltage, the loading at the output and the resonating Charge EH300/EH301/EH300A/EH301A series components on board the EH4295. The oscillator waveform is EH Modules from low voltage sources coupled to a transformer inside the module that provides an AC Energy Harvesting from low-voltage micro-power output signal that is limited in amplitude by the output loading. A energy-generating sources typical output loading is a full wave rectifier that can handle AC Direct or Indirect remote-node power supplies for inputs over 20V and input power as limited by the output of the Wireless Sensor Networks EH4295. Low duty-cycle metering, control and sensing networks Energy capture from Intermittent energy sources For many energy-harvesting applications, the EH4295, combined Trickle-charger for Standby backup power such as with EH300 Series Energy Harvesting Modules, offers a simple battery-packs or super-capacitor networks and efficient solution when used with a low-voltage low-energy Backup power for switching between different power generating source that only delivers sporadic intermittent amounts sources of input power. The combined EH4295 and EH300 Series Modules Industrial and Business systems with always-charged can ramp from zero output power to useable levels for operating temporary backup power supplies Micro-power Self-boosting oscillator Low DC Voltage Booster to supply operating voltage for another Step-up DC-DC converter ORDERING INFORMATION Extreme life-span power sources EH energy capture, storage, and power management Part Number Description from mechanical, thermal, chemical, solar, biological, and human body sources EH4295 Micropower Step Up Low Voltage Booster EH based battery substitution and/or remote battery Module, 950 Input charging systems Hybrid or alternative power source conditioning EHJ3C 6 in. Input Cable for EH4200 Series Modules Condition-based monitoring systems EHJ4C 6 in. Output Cable for EH4200 Series Modules Self-powered remote control switching systems with connector to the EH300/EH301 Hybrid power (dual power) systems with extended EHJ5C 6 in. Output Cable for EH4200 Series Modules operating lives System power reliability enhancement Intermittent duty cycle remote site applications Rev 2.1 2012 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286 www.aldinc.com E N A D E L Bmany remote sensor networks and circuits requiring DC supply FUNCTIONAL DESCRIPTION voltages in the 1.8V to 6.8V range. The boosted AC or DC output voltage levels can also be used to generate a reference DC output The EH4295 Micropower Step Up Low Voltage Booster Module is to drive or to initiate other electronic circuits such as external Power a simple but sophisticated development that thrives on ultra low Step-up DC-DC converters requiring DC supply voltages over power operation as well as ultra low voltage operation. At its core 1.0V in order to operate. is an ALD EPAD MOSFET array that is designed and developed for this application. An on-board transformer that couples to a ENERGY HARVESTING APPLICATIONS dedicated EPAD MOSFET Array forms the heart of the self-starting oscillation circuit. Featuring micro-power and highly efficient operation, the EH4295 is well suited for many EH applications that operate on low-voltage An input decoupling capacitor integrates and filters the input signal power supply or battery sources at low power levels. The EH4295 to drive the transformer primary winding core. An input ground is designed to accommodate a voltage input source that changes voltage also turns on an EPAD MOSFET Array through the in voltage and internal impedance similar to that of an EH energy connection of a resistor to its Gate Input. A current flows through generator source, such as a single-cell photovoltaic cell or a low the primary winding of the transformer, coupling and developing a voltage thermoelectric generator (TEG). corresponding current in the secondary winding. Upon being energized, a voltage develops across the secondary winding of the When input energy to an EH energy-generator source is at zero, a transformer. A small coupling resistor-capacitor network then typical DC output of the energy generator source is at a voltage that provides negative feedback from the secondary winding to drive corresponds to a zero energy output state. The corresponding the EPAD MOSFET to an off state. This RC network then charges output power of the energy-generator source is also at zero. As the gate voltage of the EPAD MOSFET until it is again in an on external energy builds up at the energy-generator source, the DC state. Once the EPAD MOSFET is turned on again, the cycle voltage at its output starts to rise from its previous state, its internal repeats itself and the circuit oscillates at a frequency that is impedance changes, and it starts to output current as well. When determined by the source generator impedance characteristics, coupled to the EH4295, the energy-generator source internal the output loading characteristics, the parameters of the RC impedance and the EH4295 input impedance form a network network, the characteristics of the EPAD MOSFET array and that where the energy-generator source starts to deliver power to the of the transformer. This natural frequency also varies with varying EH4295. As soon as the internal oscillation threshold power level input source impedance and the input voltages at the source as is reached, oscillation begins, and energy transfer is initiated. well as the changing output characteristics of the output loading. Typically this power level is less than 5W for the EH4295, and varies across different models and units. Hence the EH4295 is The EH4295 module is self-starting, and begins operating as soon excellent for high efficiency, low power applications where the as enough energy is available for the oscillator to start oscillating. minimum operating power range are very low, and where other- This minimum self-starting energy level may vary slightly from unit wise wasted energy cannot be captured and stored in a battery to unit. However, it starts boosting voltages at such a low energy pack or capacitor storage bank using other means. level that it generally can capture very low levels of energy spurts before many other industry low-voltage booster modules would As input energy builds up at the energy-generator source, the begin to function. For select members of the EH4200 MLVB Series amount of power transferred also changes accordingly. The maxi- of Modules, the oscillator can initiate oscillation at less than 1uW mum power rating of the EH4295 limits its power handling capabil- average input power. ity, but it does allow an external secondary DC-DC converter to take over at some higher power point. The AC output generated by The EH4295 primary output is an AC output, which delivers the the on-board oscillator enables the EH4295 to support other output waveforms of the oscillator. This AC output can be con- switching circuits to convert at a higher voltage and power level. nected directly to the inputs of an EH300 Series Energy Harvesting Module through a 2-wire connection. While the primary intent of the EH4295 is to charge ALD s EH300/ EH301 Energy Harvesting Modules, an optional bridge rectifier can be added on the pcb of the module by the user to produce a full- wave rectified DC output. The output of the full-wave rectifier can be used to drive an output DC load and can be useful as a trickle charger for rechargeable batteries or super-cap capacitor banks. This DC output can also be used to power an electronic circuit directly, which requires that a compatible current consumption be designed for the electronic circuit. OPTIONAL PARTS LIST Full wave rectifier - MBS Series Socket Adapter: Hirose DF13-2S Hirose DF13-4S EH4295 Advanced Linear Devices 2 of 5