Laptop Battery Power supply. Start Up Project 38

12ADon’t throw away old Laptop battery; it can be reused for other purposes. I hacked one Laptop battery and salvaged six high efficient Samsung Lithium Ion batteries each rated 3.6V, 4300 mAh. It is worth Rs. 1000. Few days before, I found that, my Laptop is not getting enough back up and shutdown immediately when the charger is removed. So I replaced the battery at the cost of Rs.1200. Due to curiosity, I just opened the case of the old battery pack and found that, the batteries inside can be reused. After testing, I found that only one battery out of the six is damaged. All the other five are in good condition. That damaged battery created the problem in the battery pack and prevented the remaining five batteries from their work. So actually this is happening in our Laptop. If one battery fails, we have to replace the battery pack. If the good batteries are salvaged from the old pack, we can reuse them for many different applications like LED lighting, Mobile charging, making power supply etc. So I spend Rs.1200 for the new battery pack but I salvaged 5 good batteries worth Rs. 1000 from the old battery pack. So my actual expense is only Rs.200. So do not discard the old Laptop battery. Tear it, salvage the individual batteries and reuse. You can save money and can reduce the e-waste.
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Regulated Power Supply Socket. Start Up Project 33

3AWhile constructing circuits on Bread board, sometimes we need a well regulated power supply. For this, we use Voltage Regulator IC. But, its needs some components and take some space in the bread board. For an easy project making, we can make a Permanent Regulated power supply board that can be hooked in the bread board. The power supply board has a 3 pin socket, so any Voltage regulator of the 78XX series can be connected in it. The power supply board has noise and transient filtering capacitors, a buffer capacitor and input and output indicators. So by plugging the power supply board in the bread board, we save time and save much space in the bread board for the circuit assembly. Easy project building makes the circuit perfect.
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Home Made Power Supply. Home Utility Circuit 27

2AThis Homemade Power supply is useful for the Electronics hobbyists and service persons to test and troubleshoot the circuits. It gives six stage well regulated output power with a current of 800 mA. Its construction is “Open type” as it is home made. You can make it like a professional power supply by fixing inside a box with connectors for tapping the output.
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Portable Power Bank. Home Utility Circuit 11

downloadHere is a simple Portable Power Bank that finds many uses. It can be used as a Portable Mobile Charger or it can be used for powering the bread board projects and so many applications that requires 5V Regulated DC. Let us make it.
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Ohms Law and Zener Resistor. Simple Design 4

Zener is a kind of Diode widely used in Voltage regulation and Switching applications. Zener is similar to other signal diodes but it conducts only if a specific voltage is provided to it based on its voltage rate. For example, a 5 volt Zener conducts only if it gets more than 5 volts. When the voltage to the zener rises above its value, its p-n junction undergoes breakdown and conducts. This breakdown point is known as Avalanche point. Unlike other diodes, current through the zener must be controlled, otherwise it will fail. So a series resistor must be connected to control the current through it. Here comes the importance of Ohms law .
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Portable Power supply. Design Note 44

Hacked my Laptop battery and charger to make a Portable power supply. My old Laptop was irreparably damaged leaving only a good battery. It is a high performance 12 volt Lithium Ion rechargeable battery that can backup more than 2 hours a laptop and many hours for circuit boards and LED lights. So I made a Portable power supply using the battery. So don’t discard the battery and charger if your Laptop fails permanently. Both battery and the charger costs around Rs. 2000.It can be utilized for making a Power supply or LED lamp. So it is the  good power supply I ever made because it is running on battery and output is fully regulated.
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Power Supply for Projects. Design Note 43

IMAGEFor bread board assembly of Micro controller and Arduino projects ,we need  well regulated  5 V and 3.3 V DC power supply. Here is the simple but efficient regulated power supply that gives four stage power outputs  – 12 V unregulated, 9 V, 5 V and 3.3 V regulated DC .
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