MAX630 solar power supply circuit using step up switching regulator

A very simple solar power supply electronic project can be designed using the MAX630 CMOS micropower step up switching regulator manufactured by Maxim Semiconductor .
Maxim’s MAX630 CMOS step up switching regulator is designed for simple, efficient, minimum-size DC-DC converter circuits in the 5mW to 5W range. The MAX630 IC provide all control and power handling functions in a 8-pin package .
This solar power supply circuit can deliver a 4.8 or 7.2 volts output voltage using a 3 volts input from a bank of photocells .

The efficiency of this solar power supply circuit is around 70% .
To chose the output voltage of the power supply regulator you need to choose the correct value of the R1 resistor . If you want that the power supply to provide a 4.8 volts at the output , the value of the R1 resistor should be around 453K ohms and if you want to obtain a 7.2 volts at the output , the value of the R1 resistor must be around 273k ohms .
The maximum current provided by this power supply circuit diagram is around 15mA .