mobile phone solar charger

[Basma Assad]

i use multisim
my solar panel gives in a sunny day 6.3 V and 8.3mA
can you help me??

 

[ericgibbs]

i use multisim
my solar panel gives in a sunny day 6.3 V and 8.3mA
can you help me??

If you get a free download of LTSpice, thats a good simulator, little difficult to learn, but good.


8.3mA!.. that dosnt sound correct, how big is the panel.??

 

[Basma Assad]

Ltspice how can i get it??

and what is wrong with the value 8.3mA my panel is too small

 

[Sceadwian]

Linear Technology - LTspice IV Downloads and Updates

 

[ericgibbs]

Ltspice how can i get it??

and what is wrong with the value 8.3mA my panel is too small

What are the dimensions of your solar panel.?

 

[Basma Assad]

9.5 X 7.0 cm

 

[ericgibbs]

9.5 X 7.0 cm

I would expect more than 6.8mA in sunlight. Say 50mA+

 

[Basma Assad]

ok, maybe i measure it in a wrong way

can you help me with circuit.

 

[blueroomelectronics]

Maybe it's a homemade panel from doughnuts & tea.
**broken link removed**

 

[Basma Assad]

actually it is not homemade solar panel and i got from germany and lets focus on the problem (the circuit please)
what is wrong with my circuit.

 

[blueroomelectronics]

What is the battery rating on your phones battery? Voltage & mAh

 

[Basma Assad]

5.7 V and 800mA

 

[blueroomelectronics]

Your solar cell charger is going to take days/weeks to charge the phones battery. It's current output is at best 6.3V @ 8.3mA (0.05W) and your phones battery is 5.7V @ 800mA (4.5W). Plus you're boosting the panel to 9V (if you're lucky it's >80% efficient)
What power output does the charger that came with the phone put out?

 

[Basma Assad]

i don't understand your question?
the charger gives the phone 5.7V and 800mA
the output power would be 5.7*800m

 

[blueroomelectronics]

Alright, so the CHARGER says 5.7V @ 800mA then that's what the phone will want, where did you get 9V from?

Anyway you'll need a 5W solar panel preferably > 8V out so a simple 5.7V buck converter to 5.7V is you need.

 

[Basma Assad]

i have used the circuit that collins posted and it gives me a varying output (10.7 v to 11.7 v ) from a 3 v input (i mean in the simulator) but i still worried that it will fail since it's varing to values and when i tried to put zener diode to regulate the output the circuit doesn't work (it's started to go slowly)

 

[blueroomelectronics]

It's simply not a powerful enough a solar cell for what you want it to do.

 

[Basma Assad]

i gad to do it using this solar cell i've got 4 of it
but again my problem is what is wrong with the circuit can anybody answer this question???

 

[Sceadwian]

What circuit? I see no circuit anywhere in here.

 

[Basma Assad]

if you bother yourself and look at the attachemnet in the first post you'll find a circuit .
and tell me if you please what is wrong with it , and what is wrong with the circuit that collins post it ?