simple solar circuit

[jimmyhackers]

i got one of those cheap solar 4 in 1 robot toys. makes a little dinosaur and other things.

i was wanting to make some kind of small storage/boost circuit for him as hes pretty terrible.
currently he is just a motor hooked directly to the small solar panel. in anythign other than blazing light he doesnt move.

my idea is to make a very simple circuit that would charge up what little power the panel has in a capictor. then once the voltage is high enough it would discharge it all into the motor for a quick small boost of motion.

ive tried faffing in yenka cicuit design program but i just cant get it to work with various gates. can someone tweak my given circuit or give me a better one. the smaller and simpler the better.

thanks in advance
jim

 

[billvon]

can someone tweak my given circuit or give me a better one. the smaller and simpler the better.

Your problem is going to be that at .5 volts (what you get out of a single cell) you are going to be hard pressed to do any sort of a timer. Consider something like this: https://www.digikey.com/product-detail/en/sparkfun-electronics/PRT-10255/1568-1155-ND/5673741

It's a boost converter designed for use with single cells. This will get you 3.3 or 5 volts out. From there you can do a simple voltage threshold detector with some hysteresis. Use a low voltage comparator to turn on a switch or small relay at (say) 3.3 volts and off at 2.5 volts.

To calculate comparator resistor values take a look at: https://www.daycounter.com/Calculators/Comparator-Hysteresis-Calculator.phtml. Use very high value resistors.

 

[jimmyhackers]

haha, they do make them

they are called energy harvester circuits ltc3588

https://www.ebay.co.uk/itm/143442907104?_trkparms=amclksrc%3DITM%26aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3Ded75d3b67178457badb5dadb97588ae7%26pid%3D100675%26rk%3D3%26rkt%3D15%26sd%3D134033185238%26itm%3D143442907104%26pmt%3D0%26noa%3D1%26pg%3D2380057%26brand%3DUnbranded&_trksid=p2380057.c100675.m4236&_trkparms=pageci%3A4472024c-94d5-11ec-9ebb-7a6d4a6f663e%7Cparentrq%3A27d0198e17f0a9d9919ec9e1fff60674%7Ciid%3A1

kinda pricey though :S

 

[jimmyhackers]

i found the original circuit aswel...

https://www.instructables.com/Make-a-Solar-Powered-Bug-Robot/

can buy over 10 sets of the components needed for this circuit....for the same price as one of those energy harvesting modules.