You can't design a charger from no load spec's. You need to know the charging voltage and current of the battery, the operating voltage and current of the phone and the solar panel's max output and average output voltages and currents.

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Uncle $crooge

 

solar panel max voltage is 5.4v,current is around 300mA
& load wat i need to charge is cell phone, voltage is 3.7v-5.4v,350mA-500mA
so, wat i need to do or know next step?? thx ur helping & teaching

 

Ask your teacher why he isn't teaching you about this stuff.

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Uncle $crooge

 

Oh no, certainly not a teacher. He is a lecturer so "miaomiaooh" is in university or college for sure. Lecturer don't teach but ask you to look it up yourself, or as one user said, points you to this very forum.

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L.Chung

 

so,if i want to measure the maximun output current of a voltage regulator by connected a DC power supply, how can i measure it??
thanks for all of you

 

Measure Amps as follows:

Note, this is at the low voltage side of the charger.

+ (charger) to 10Amp terminal(DMM).
Common terminal(DMM) to load(cellphone battery).
Leave negative (-) as is.

Measure volts

+ to volts terminal.
- to common terminal.

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There are more ways to get to Rome.

Electricity, Electric clocks, Meters and Trains are great.

 

This might be trivial but keep in mind that the insertion of the current measurement instrument (likely to be a DMM) may result in a change in the operation of the load - since a slight but measurable voltage drop can result. As already implied - measure the current and voltage - and I would encourage measuring both at the same time (requring a second DMM or other meter).

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stevez

 

My teacher in high school taught and demonstrated how to use a multimeter.
My neighbour also demonstrated how to use a multimeter.

Years ago, universities had professors who actually taught the students, not a puppet lecturer who just reads stuff like today.
Students asked the prof questions that were answered by him, not by guys on a forum.
What has become of education today???

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Uncle $crooge

 

There are numerous publications that do a great job at explaining how to make these measurements. The publications may be in the form of a book, journal or magazine article or on-line source. If you are attending a university I would expect the library to have plenty of these publications. I would encourage you to review several of these. They are likely to offer a complete picture with diagrams and explanations that match the diagrams. You might still have a few questions that can be handled by the forum.

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stevez