Solar Powered, LiFePO4 Battery Backed-Up 3.3 or 5 Volt Switching Regulator
mmowen
Posts: 38
Open source, solar powered, 3.3 or 5.0 volt, regulated power supply using off board photo-voltaic cells to supply charging current to one or two lithium iron phosphate (LiFePO4) 0.6 amp hour battery cells mounted in standard AA size holders on the board. Output regulation is accomplished using a TI buck/boost topology switching regulator which may be disabled during charging. Headers are included for monitoring solar, battery and output voltages using a Basic Stamp or Propeller micro-controller unit (MCU). When the system is disabled (shutdown) the leakage current is less than 10 micro amps (regulator spec sheet says 1uA), not generally even measurable with most hand held multi-meters. This power supply can be used to power virtually any 3.3 or 5.0 volt device which requires less than one amp of continuous direct current.
It includes monitoring pins for the solar cell voltage, battery voltage and output voltage. It also includes a power saving feature for low current operations and the ability to shut the power supply output off while charging, both capabilities can be set with jumpers, a double pole toggle or rocker switch, or can be driven with external circuitry (eg: a micro-controller).
Weights:
Circuit board and batteries: 55 grams
Small solar cell pair: 42 grams
Large solar cell: 87 grams
Dimensions:
Circuit board and battery pack assembly: 66mm x 30mm x 37mm
Basic configuration includes:
1 - Circuit board containing AA battery holders, switching regulator and related components
2 - 600mAH LiFePO4 14505 AA battery cells
3 - Jumper clips for on board option selections
Available as add-on options:
Various solar cell configurations
A self powered 2.5-33 miniature voltmeter
A 4D Systems 128x128 pixel 16 bit color display with micro-controller (comes pre-programmed as a voltmeter but you can reprogram it any way you wish with the free 4D Systems development tools from 4DSystems.com.au)
Want one? I have them listed at https://www.tindie.com/products/mmowen/photon-to-electron-transmutator/
It includes monitoring pins for the solar cell voltage, battery voltage and output voltage. It also includes a power saving feature for low current operations and the ability to shut the power supply output off while charging, both capabilities can be set with jumpers, a double pole toggle or rocker switch, or can be driven with external circuitry (eg: a micro-controller).
Weights:
Circuit board and batteries: 55 grams
Small solar cell pair: 42 grams
Large solar cell: 87 grams
Dimensions:
Circuit board and battery pack assembly: 66mm x 30mm x 37mm
Basic configuration includes:
1 - Circuit board containing AA battery holders, switching regulator and related components
2 - 600mAH LiFePO4 14505 AA battery cells
3 - Jumper clips for on board option selections
Available as add-on options:
Various solar cell configurations
A self powered 2.5-33 miniature voltmeter
A 4D Systems 128x128 pixel 16 bit color display with micro-controller (comes pre-programmed as a voltmeter but you can reprogram it any way you wish with the free 4D Systems development tools from 4DSystems.com.au)
Want one? I have them listed at https://www.tindie.com/products/mmowen/photon-to-electron-transmutator/
855 x 570 - 126K
855 x 570 - 542K
855 x 570 - 141K