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Battery Charger Circuits
12 volt car battery charger circuit schematic
Unlike many units, this battery charger continuously charges at maximum current, tapering off only near full battery voltage. In this unit, the full load current of the supply transformer/rectifier section was 4.4A. It tapers off to 4A at 13.5V, 3A at 14.0V, 2A at 14.5V and 0A at 15.0V..
a friendly charger schematic for mobile phones
Most mobile chargers do not have current/voltage regulation or short-circuit protection. These chargers provide raw 6-12V DC for charging the battery pack. Most of the mobile phone battery packs have a rating of 3.6V, 650mAh. For increasing the life of the battery, slow charging at low current is advisable. Six to ten hours of charging at...
battery charger regulator
Most off-the-shelf car battery chargers cannot not be left connected to the battery for long periods of time as over-charging and consequent battery damage will occur. This add-on circuit is placed in series with the battery being charged and is powered by the battery itself. In effect, the circuit uses a high-current Mosfet to control the...
in car charger and switcher circuit for sla battery
The SLA battery is charged from the vehicle s battery. When the engine is running, the voltage remains fairly constant, which greatly simplifies the charging circuit. If the SLA battery is fully charged, any further charging current from the vehicle battery is limited by a 3.3W 5W resistor (R1). If the SLA battery is deeply discharged, the...
lithium polymer peak charger
This circuit was developed to charge the Lithium-Polymer cells used in a model aircraft. Lithium-Polymer cells are incredibly lightweight compared to Ni-cad battery packs of the same voltage and amp-hour rating. Their only drawback is that they require a rigid charge and discharge regime to achieve maximum life..
mobile cellphone battery charger circuit
Charging of the mobile phone, cellphone battery is a big problem while traveling as power supply source is not generally accessible. If you keep your cellphone switched on continuously, its battery will go flat within five to six hours, making the cellphone useless..
mobile phone battery charger circuit
Mobile phone chargers available in the market are quite expensive. The circuit presented here comes as a low-cost alternative to charge mobile telephones/battery packs with a rating of 7.2 volts..
nicd battery charger with reverse polarity protection
This NiCd battery Charger can charge up to 7 NiCd batteries connected in series. This number can be increased if the power supply is increased with 1.65V for each supplementary battery. If Q2 is mounted on a proper heatsink, the input voltage can be increased at a maximum of 25V. Unlike most of comercial NiCd chargers available on the market,...
nimh and nicd battery charger circuit
This automatic NiCd charger for 9V NiCd batteries is using 555 timer properties and is very easy to build. Why is an automatic 9 volts NiCd battery charger? Because you can leave the battery for charging as much as you like: it will be always completely charged and ready for use when is needed. It wont be overcharged and it will not discharge....
6v 4.5ah battery charger circuit
Article about full automatic 6V 4.5AH battery charger circuit with schematic using IC LM317T and few components. The circuit can charge 6V lead acid battery. ..
automatic nimh battery charger circuit
Schematic and description of simple automatic NiMH battery charger circuit using IC 7805 with multiple selectable current options for charging. ..
car battery charger
A car battery charger schematic & description . This 12v automatic car battery charger circuit can be also use for charging other automobiles batteries. ..
diy solar cell phone usb charger
Here is the schematic of a simple DIY solar cell phone or USB charger circuit. This solar USB battery charger circuit can be used to charge any device, which can be charge from computer USB port. For example MP3 players, cell phone, iphone etc. The circuit is using a solar panel of 7 to 7. 2 volts, one diode and four Ni-MH rechargeable batteries of
lead acid battery charger circuit
Lead acid battery charger schematic using IC LM317. This lead acid battery charger circuit is simple to build and can be fit in a small box. ..
li ion battery charger circuit
This article describes a circuit of simple single cell li ion battery charger or lithium ion battery charger. Using the LP2391 regulator IC..
nicd battery charger circuit
Nicd battery charger schematic and description. This Nicd battery charger circuit can charge 12V, 6V, & 9V battery packs. ..
nicd battery charger schematic
The circuit is able to charge 2. 4V, 4. 8V, and 9. 6V NiCd batteries. The LM317T IC showed in this NiCd battery charger schematic is use to regulate the voltage to battery charge the NiCd batteries as you know that the LM317T IC is a very popular IC from many years, it is a cheap IC with many built in features like current limiter, built in...
nicd nimh battery charger circuit
Schematic and description of a simple and easy to built NiCd and Nimh battery charger circuit which is able to charge multiple NiCd and NiMH batteries. ..
solar battery charger circuit
Solar battery charger schematic & description. This solar battery charger circuit can charge 12v lead acid battery or sla battery. ..
usb car charger
This is a project of a mini USB car charger circuit. The circuit is very simple to build using only three components. Heart of the circuit is a LM78M05 IC which is a 5V positive voltage regulator IC. This IC has many built in featuers like thermal overload protection, short circuit protection, safe operating area protection etc. The circuit can b
Portable battery powered USB charger circuit or schematic using IC LM7805. The circuit require only few components. ..
Fast Portable USB Charger
Powered by LM2700 IC, this charger can help you to re-charge your mp3 player, camera, cell phone, and any other gadget you can plug into a USB port with faster rate..
Solar Panel Based Charger And Small LED Lamp
You can save on your electricity bills by switching to alternative sources of power. The photovoltaic module or solar panel described here is capable of delivering a power of 5 watts. At full sunlight, the solar panel outputs 16. 5V. It can deliver a current of 300-350 mA. Using it you can charge three types of batteries: lead acid, Ni-Cd and Li-io
Simple battery charger circuit and battery level indicator with low battery recharge alarm
This is a simple 12V rechargeable smart battery charger circuit. You can use this best battery charger circuit as car battery chargers, Inverter battery charger, Emergency light battery charger etc. An automatic indicator alarm circuit also comes along with this battery charger schematic. The main advantage of this indicator is that a buzzer infor
12v Battery Charger Circuit with Auto Cut off
This is a simple DIY charge controller schematic posted in response to a request by one of our readerson our facebook page. The main component of this auto battery charger circuit is a 555 timer which compares the voltage in the battery. It turns ON the charger if the battery voltage is below the variable preset voltage (12 volt chosen here) and
24V lead acid battery charger circuit
This lead acid battery charger circuit is designed in response to a request from Mr. Devdas. C. His requirement was a circuit to charge two 12V/7AH lead acid batteries in series. Anyway he did not mentioned the no of cells per each 12V battery. The no of cells/battery is also an important parameter and here I designed the circuit assuming each...
Battery charger circuit using L200
A very simple battery charger circuit having reverse polarity indication is shown here. The circuit is based on IC L200. L200 is a five pin variable voltage voltage regulator IC. The charging circuit can be fed by the DC voltage from a bridge rectifier or center tapped rectifier. Here the IC L200 keeps the charging voltage constant. The charging...
Battery charger circuit using LM317
Here is a simple but effective battery charger circuit using IC LM 317. The circuit can be used to charge 12Vlead acid batteries. The circuit is very simple and can be easily assembled on a general purpose PCB. The heart of the circuit is IC LM 317, which is an adjustable voltage regulator IC. The pin 1 of the IC is the control pin which is used...
Battery charger circuit using SCR
A simple battery charger based on SCR is shown here. Here the SCR rectifies the AC mains voltage to charge the battery. When the battery connected to the charger gets discharged the battery voltage gets dropped. This inhibits the forward biasing voltage from reaching the base of the transistor Q1 through R4 and D2. This switches off the...
Battery charger using LM350
Here is a simple circuit using IC LM 350, which can be used for charging 12V lead acid batteries. This circuit is perfect for constant charging 12V lead acid batteries. The circuit is designed as a constant voltage source with a negative temperature coefficient. The transistor Q1 (BD 140) is used as the temperature sensor. The transistor Q2 is
Car battery charger
Given below, is a very simple circuit that can be used for charging car batteries. In this circuit there is facility for monitoring the charging current and voltage. The circuit is based on the IC MC78T12ABT from Freescale. The IC is nothing but a 7812 in TO-3 package with 3A capacity. The transformer T1 steps down the mains voltage and diodes D1&D
Lead Acid Battery Charger Circuit
A simple lead acid battery charger circuit with diagram and schematic using IC LM 317,which provides correct battery charging voltage. This lead acid battery charger should be given an input 18 Volts to IC..
Free Energy Circuits
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Solar Cell Circuits
Current Limiting Circuits
Micro Power Circuits
High Voltage Circuits
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Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
Digital Signal Integrity
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