In order to learn more about the technology of solar lawn lights, we consulted and discussed about solar lawn lights technology with 26 factories in china and we also test several samples in the market. Some problems were found during the test and the most obvious one is the operation efficiency of the lights. The start up condition, brightness and lighting time vary from each other among the same products under the same condition, and the biggest difference is around three times.   It shows that the product property is not consistent.

The solar lawn lights mainly consist of control circuit, solar panels, LED, rechargeable battery and lamp enclosure, and the key part is control circuit which directly decides the operation condition in various ways. After fully research, we calculate the optimum data by analyzing the circuit principle of the lights and comparing parameters of the product whose maximum power dissipation is below 1v.  Based on this data, we designed a new controller integrated charging circuit, driving circuit, photosensitivity controller and frequency conversion modulation circuit. It greatly improved the operation efficiency and consistent of the performance of solar lawn lights. The following parameters and properties of the controller are for your reference.

Product Name: LED driving chip (IV0101)

Keywords:       Electric Components  DC-DC Converse Chip, Semiconductor Chip  Integrated Circuit, LED Driver

Description:    IV0101 is low static electric circuit ,  DC-DC Converse Chip, proving ideal converse for the application equipment of alkaline cell and .

Ultra-low quiescent current 36uA

3.6V input 4.5V output or 2.4V input 3.3V output, 400mA output electric current

1.2V input 3.6V output, 100mA output electric current             

91% efficiency output from two batteries to 3.3V

High input voltage 0.9V-5.5V

3.3V fixed or adjustable output

Synchronous Rectifier: 0.4Ω

Switch resistance：0.4Ω

High current protection inductor

Logic close controlling

Self-lock under voltage of 0.85V
Induction under low voltage
The lowest operation voltage may be 0.9V when there is one battery applied
High efficient converse, as high as 93%
PFM＋PWM applicable to various load
Maximum Load Current is 350mA
Bonding: SOP8L

Solar Energy Electric Power Generating System Principles and Design Considerations  

 

Electric power generating system consists of solar panels, solar controller, rechargeable cell. Inverter is also needed if the output power is 220V or 110V AC. Function of each section is as follows.

 

 It is the core part in this system and also is of the highest value. It is used to convert the energy of sunlight into electric energy or store it in the rechargeable battery or make load work. The cost and quality of solar panels directly determine the cost and quality of the whole system.

 

 Its function is to control the operation condition of the whole system and it may also protect from overcharge or over discharge. Qualified controller should also have the function of temperature compensation in the place where the temperature difference is considerable. Other functions such as photo switch and time switch should also be the optional function for controller.

 

Usually it is lead acid battery, and nickel-hydrogen dattery, nickel-cadmium battery and lithium battery may be used in small system. It is used to store electric energy generated by solar panels in sunlight time and release it when needed.

 

On many occasions, 110V 220V AC is needed to be supplied. But the direct output of solar energy generally is 12VDC, 24VDC, 48VDC, so DC-AC inverter is needed to convert DC into AC in order to supply electric energy to electric appliances of 220VAC. In some instances, DC-DC inverter is also needed when various voltage loads is needed, eg.  converting electric energy of24VDC into 5VDC (it is not simple voltage step-down)

 

A Where the system will be used? What’s the solar radiation condition?

B How big is the load power of the system?

C The output voltage amount should be taken into account and is it AC or DC?

D How long does the system need to work per day?

E How many days are required to generate power continuously if it is stormy or cloudy days？

F The condition of the load, pure resistance character, capacitive character and inductive character need to be considered, and how much is the starting electric current?

G How many systems are needed?