Cicuit board design

[yammers]

Hi there i am a complete novice and was wondering if there is anyone out there who can help me design a circuit board schematic.

i am looking for something that will include the followng

1. in puts for connecting solar panels to it and usb input for chariging
2 lithium iron charging
3 protection for the solar panel and battery
4 5v booster with usb output for connecting to a 5v usb led light strip

led lights would come on when natural light would disappears and capacitors to help store charged power to help power lights in winter

this is for a garden solar led light project

I have seen boards that have the charging such as the tp4036 and booster as individual boards but not combined,

 

[(*steve*)]

First step is to design the circuit. Have you done that?

 

[yammers]

No cause i dont know how to do this

 

[(*steve*)]

Ok then you need to design a circuit first. A PCB is only designed after you have the circuit.

Do you know:

1. The amount of energy you wish to store in a full charge,
2. The battery voltage (effectively defined by the number of cells in series),
3. Your maximum load current, and
4. Details of the solar panels?

Did you say you also want to charge this device from USB? (Your point 1)

 

[kellys_eye]

No cause i dont know how to do this

Just a point of note - what you are requesting (i.e. for 'us' to do the design work) would usually cost upwards of £75-£150/hour from professional services.

This is not something that the forum is meant for although there may be some willing members prepared to do this for you - they may even request payment too!

What we're more likely to do is help you achieve the end result by your own means which will result in us giving you as much information as necessary for YOU to finish the job.

If you're here expecting a 'turn-key' solution you may be disappointed.

Question - are you willing to do some research, design and construction using our advice?

 

[yammers]

If i am honest know i know i am looking for a solar panel to charge etiher two 1860 batteries or a mobile phone battery to out via a booster to put out at 5v to power led 5v led light strip. not sure what batteries or panel i would need

 

[kellys_eye]

You have (almost) all the information in that very statement.....

1. Solar cell - find one that you think suits (is size important? - giggidy)
2. 18650 - in series or in parallel?
3. booster - otherwise known as a 'buck' (step-down if using 2 x 18650 in series) or 'boost' (step-up if using 2 x 18650 in parallel) converter. Search eBay for buck and boost converters with 5V output and 18650 input.

I think I've actually seen a single circuit board that has a solar cell input, 18650 charge circuit AND a 5V regulator on eBay!!!

I searched eBay using 'solar 18650 5V' as the search and found this:

https://www.ebay.co.uk/itm/3-5W-5V-...651857?hash=item1a4f3e97d1:g:QkQAAOSw30Ja~TIG

Might not be 'exactly' what you want but you can keep searching using that search term or modify it to see if anything more suitable comes up.

You won't be able to build one cheaper than you can buy one.

 

[(*steve*)]

Ok. I presume you mean 18650 batteries.

When you said lithium iron, did you mean LiFePO4, or lithium ion? Or don't you actually care? If you already have the batteries it will make a difference.

Your phone may require around 10Wh to charge it. A single high quality lithium ion 18650 cell stores this amount of energy, but you'll need 2 to allow for various losses.

So that leaves little for the LED strip. Do you want to do one or the other? If so, the same batteries could power a typical LED strip that draws 1A for three hours or so.

Is that what you're after? And how fast do you need it to charge from the sun? A 10W panel should do it in a day (faster in summer, possibly marginal on a clear winter's day).

 

[yammers]

well ive seen youtube video of two solar cells powering usb 5v led strip so maybe x2 3.5 watt cells etc. looking for it to charge during day maybe using amorpus cells. would adding a charge booster or capaciters allow for longer run time and i think i would wire them paralell. looking a amorphous cells

 

[MidNor]

I am just wondering... In certain cases where you have a common requirement like solar.
Won't it be cheaper and better to buy the charger rather than risking damaging equipment?