I'm in the process of developing a pocketqube and I am currently working on the power system. I am hoping to use an SPV1040 MPPT IC to simplify the design and maximize efficiency. Each side of the craft will have 8 Trisolx GaAs solar cells with an open voltage of 2.6 V and max power voltage of 2.3 V, they have a max current of 14.6 mA. Obviously all these characteristics are in a direct sunlight ideal scenario at ambient temperature. The battery charged will be a 700 to 900 mAh 3.7 V Li-Ion and the output voltage needed is 3.3 V.

The following schematic here displays an output voltage of 5 V though I cant find what resistors I need to change to adjust that. enter image description here

Here is the datasheet http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00287506.pdf

Input also says 3 V though the IC is rated to 0.3 V, how can I change that?

Also on a last note I plan to use 1 MPPT circuit for each panel, if I put 4 parallel cells in series with another (basically 1 panel) what diode should I use between the series cells?

  • \$\begingroup\$ This is a question and answer site and not a place to request collaberations. As such your question is unclear. \$\endgroup\$
    – Andy aka
    Jul 8, 2018 at 11:16
  • \$\begingroup\$ My bad, changed the question, there's a ton of questions so I didn't really want to create a huge question. Sorry for the disturbance & Thanks! \$\endgroup\$
    – Julianfer5
    Jul 8, 2018 at 11:34
  • \$\begingroup\$ @Julianfer5 - (a) "IC is rated to 0.3 V" Where exactly did you see that stated, please? There's a misunderstanding or error somewhere. (b) Please add a link to the schematic which you included, as that isn't in the datasheet and readers may want to see more context from the original source. (c) I'm unclear about something that might be a question within the text (without a question mark). You seem to be asking how to make the SPV1040T output 3.3V, instead of the 5V on the schematic, in order to charge a Li-Ion battery. Please edit the question text to clarify. \$\endgroup\$
    – SamGibson
    Jul 8, 2018 at 20:53
  • \$\begingroup\$ @SamGibson Made a new question and will delete this one, I figured it out. New question with more info is here: electronics.stackexchange.com/questions/383763/… \$\endgroup\$
    – Julianfer5
    Jul 8, 2018 at 21:24
  • \$\begingroup\$ @Julianfer5 - Thanks for explaining. Although there can be times when deleting a question may be the best option, doing that too often can get you a bad reputation for wasting people's time. It's not just the reading time that's lost, it's the cognitive effort to understand it, form a mental model of the system, consider possible solutions to the question(s) asked etc. etc., all of which is wasted effort, if a question is deleted. Some members don't help people who delete questions, to avoid having yet more time wasted. So please try to get the question right first time :-) Sincere good luck! \$\endgroup\$
    – SamGibson
    Jul 8, 2018 at 22:33