Battery Charger Circuits |
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The simple circuit below regulates the voltage from a 6v solar panel to a fixed +5v. That voltage can be fed to any cell phone or USB connected portable device, to charge its battery. The circuit uses a Reg113-5 voltage regulator from Texas Instruments. The tiny device can handle up to 400ma of charging current. I would suggest using a solar... .
This project, which can charge a pair of AA Nickel Metal Hydride (NiMH) or Nickel Cadmium (NiCd) cells using a laptop`s USB port for power, arose to address part of that problem. (By the way, if you want to lighten your laptop load, take a look at the MoGo Mouse. ) Any USB port can supply 5V at up to 500mA. The USB standard specifies that a... .
Here we provided several schematic drawings of battery charger circuit. These circuits covered 5W~200W NiCd, NIMH, Lead-Acid, and Li-Ion/Polymer, LiFePo4 battery packs. We hope chargers circuits files can help our users to select correct chargers also can help them to get a good understanding about our products. .
Rectifted and filtered voltage from the 24 Vac transformer is applied to the LM723 voltage regulator and the npn pass transistor set up for constant current supply. The 470 ohm resistor limits trickle current until the momentary pushbutton (S2) is depressed, the SCR turns on and current ftows through the previously determined resistor network limi .
When power is applied to the circuit, SCR1 is off, so there is no bias-current path to ground; thus, LM317 acts as a current regulator. The LM317 is connected to the battery through steering diode D1, limiting resistor R1, and bias resistor R2. The steering diode prevents the battery from discharging through the LED and the SCR when power is remov .
The circuit is built around an LM317T adjustable voltage regulator. Its output voltage (VOUT) is determined by the formula VOUT= l. 25 (1+R2/R1). I chose a 10-k © resistor for R1 and a 100-k © resistor for R2 to allow for a little wasted current flow (around 125 A). This will develop 13. 75 V between the output terminal and ground. R3 and a diode .
Whatever past project these were used in obviously required three cells to be wired in parallel with a rather large (4700 uF) capacitor on a perf board. There were 13 of these board assemblies, for a total of 39 solar cells and 13 capacitors (not to mention the 13 perf boards themselves). The cells themselves are about 2. 25 inches square, and... .
This circuit lets you keep the appliances plugged into your inverter. It won`t make the wind blow or the clouds go away, but it will keep your batteries safely charged even if you have a generation shortfall. I call it the Grid Charger Voltage Switch. The circuit utilizes a PIC microcontroller to monitor battery voltage and control a solid state... .
This circuit may be used to replace the single current limiting resistor often found in dirt cheap battery chargers. The alternative shown here will eventually pay off because you no longer have to throw away your NiCds after three months or so of maltreatment in the original charger. The circuit diagram shows an LM317 in constant-current configur .
The design of the charger is similar to that of many commercially available chargers. The charger consists of a mains adaptor, two resistors and a light-emitting diode (LED). In practical use, this kind of charger is perfectly all right. Resistor R1 serves two functions: it establishes the correct charging current and it drops sufficient voltage t .
A simple NiCd charger can be built using junk box` components and an inexpensive LM317 or 78xx voltage regulator. Using a current limiter composed of R3 and a transistor, it can charge as many cells as desired until a fully charged` voltage determined by the voltage regulator is reached, and it indicates whether it is charging or has reached the f .
This very simple circuit uses a transformer, two diodes, a capacitor and an ammeter. To charge a battery just connect the + and terminals of the circuit to the corresponding terminals of the battery. When the battery is not charged, the ammeter reading shows 1-3 amps. When the battery is fully charged the ammeter reads Zero or nearly zero, af .
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