Overview
Reversed engineering is referred to as the process of producing or creating another object following a detailed specification, construction, composition, and examination of the object’s existing components. Other definitions also include going through the development cycle in backwards and discovering the mechanism of an object by taking it apart and assembling back components with a new or manipulated function.
Project Specifications
For this reversed engineering project, the objective is to Increase the lamp’s current 3.3 voltage to 5.1 volts to brighten LED illumination. The electronic piece of equipment to be sampled for this project is a garden lamp, which is a simple lamp and a very affordable piece of electronic that uses solar energy to power its light emitting diode (LED). The lamp can be purchased from a dollar store for only a dollar a piece. Given that the lamp is solar powered, it is interesting to know ifs normal voltage capacity can be further improve to optimize the capacity of the LED light to shine brighter.
The main component to be reversed engineered in the garden lamp is the circuit where the voltage regulation takes place. The model used for the project’s schematic encompasses charge pump function where the discreet components are being manipulated to yield the desired voltage output of the LED light. The garden lamp is composed of very simple and circuit with less components to be altered. The external parts of the lamp are composed of a plastic top cover that incases the entire circuitry and the main electrical components. The Top part of the lid is where the 3v 20ma solar cell was mounted to charge the AAA 1.2v 600mAh Ni-MH battery where the power of the lamp will come from when turned on at night.
The interior of the garden lamp utilizes the 3v 20ma solar cell and van reach up to 3v maximum in bright daylight. The solar cell is soldered to the – and + terminals of Ni-MH AAA battery rated 1.2V at 600ma where the power collected by the solar will be stored until night time or when the lamp is tuned on. In addition, there is also a small circuit board a transistor labeled with YX818 chip with four pins is attached. It is confusing at firs that the battery is only rated at 1.2v, but given the presence of the transistor, it is apparent that the voltage can still regulated or increased because the YX818 chip is acting in two ways one is to drive the voltage up to the LED or bring it back down to 1.2v.
The technical operation that takes place around the small circuit board is rather more complex that anticipated. The 8018 chip also acts as the on and off switch of the lamp where the LED and solar cell is attached to the chip where the positive output produced by the solar cell passes through the battery’s positive terminal while the other end goes to one of the chip’s pins. During daytime, the light that passes through the solar cell is placed into the chip’s negative CE that switches the LED off allowing the electrical charge to go directly to the battery to recharge. As soon as daylight passes, the negative CE will disengage and electric current will pass through both the negative and positive pins of the CE going through the capacitor turning on the LED.
There are no special materials used in the project except for a load meter, which is necessary in measuring the voltage yield. A circuit modification was made as shown in the below schematic;
The result of modifying the circuit of the garden lamp has resulted to a yield of 5.1 volts after a load test. Adjusting the potentiometer was able to provide.424 ma at 4 volts showing a load resistance of 9.4kΩ. All the materials used in this project including the capacitor, battery, LED, transistor, and even the garden lamp itself can be purchased from everyday hardwarer store and in the dollar store for a very minimal cost ranging from $1 to $2 a piece. The printed circuit board on the other hand is unique ti the manufactiurer of the garden light. Reverse engineering often requires PCB to achieve the modification outcome. Re-engineering PCB’s and its component can essentially provide added performance to the electrical product. Simple rewiring and re-work on the other components attached to the PCB can essentailly affec the functional behavior of the electronic product. In this project, the reworking on the circuit itself enabled the gaden light LED to use higher voltage for a greater luminousity. On the other hand, the modified garden lamp cannot be used other than its intended purpose due to patent issues the reverse engineering often entails. The project encompasses a simplified exercise showing the practical application of electronic engineering where simple circuits in electronic appliances can be modified for optimum functionality.
Works Cited
Eilam, Eldad, and Elliot J. Chikofsky. Reversing: Secrets of Reverse Engineering. Indianapolis, IN: Wiley, 2005. Print.
