Simple 12 V Battery Charger Circuit Diagram

This 12 V Battery Charger Circuit Diagram is a high performance charger for gelled electrolyte lead-acid batteries. Charger quickly recharges battery and shuts off at full charge. Initially, charging current is limited to 2A. As the battery voltage rises, current to the battery decreases, and when the current has decreased to 150 mA, the charger switches to a lower float voltage preventing overcharge.

 12 V Battery Charger Circuit Diagram

When the start switch is pushed, the output of the charger goes to 14 V. As the battery approaches full charge, the charging current decreases and the output voltage is reduced from 14 V to about 12 5 V terminating the charging. Transistor Ql then lights the LED as a visual indication of full charge.

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USB Powered Mobile Phone Battery Charger Circuit

Description 

 This simple circuit can give regulated 4.7 volts for charging a mobile phone. USB outlet can give 5 volts DC at 100mA current which is sufficient for the slow charging of mobile phones. Most of the Mobile Phone batteries are rated 3.6 volts at 1000 to 1300 mAh. These battery packs have 3 NiMh or Lithium cells having 1.2 volt rating. Usually the battery pack requires 4.5 volts at 300-500 mA current for fast charging.

But low current charging is better to increase the efficiency of the battery. The circuit described here provides 4.7 regulated voltage and sufficient current for the slow charging of the mobile phone. Transistor Q1 is used to give the regulated output. Any medium power NPN transistor like CL100, BD139, TIP122 can be used. Zener diode D2 controls the output voltage and D1 protects the polarity of the output supply. Front end of the circuit should be connected to a A type USB plug.

Connect a red wire to pin1 and black wire to pin 4 of the plug for easy polarity identification. Connect the output to a suitable charger pin to connect it with the mobile phone. After assembling the circuit, insert the USB plug into the socket and measure the output from the circuit. If the output is OK and polarity is correct, connect it with the mobile phone.

Circuit Diagram:

Parts

• Q1 = BD139
• D1 = 1N4001
• D2 = 4.7V - 1/2W
• R1 = 560R - 1/2W
• C1 = 16V - 100uF 

 Note:
 If the polarity is incorrect, it will destroy the mobile battery. So take extreme care.

Source - http://www.extremecircuits.net/2010/02/usb-powered-mobile-phone-battery.html

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Car Battery 12v Charger

The usual chargers of battery automotive, are simple and cheap appliances that charge continuously the battery, with a rythm of few amperes, for the time where the appliance is ON. If the holder do not close in time the charger, the battery will overcharge and her electrolytic faculty are lost with evaporation or likely exists destruction of her elements. The charger of circuit exceeds these faults. It checks electronic the situation of charge of battery and it has circuit of control with retroaction, that forces the battery charge with biggest rythm until charge completely. 

 

Circuit diagram:

Car Battery 12v Charger Circuit Diaram

When charge completely, it turns on one RED led (LD2). The charger has been drawn in order to charge batteries of 12V, ONLY. What should watch it from what it manufactures the circuit, they are the cables that connect the transformer with the circuit and in the continuity the battery, should they are big cross-section, so that heat when it passes from in them the current of charge and also they do not cause fall of voltage at the way of current through them.

Adjustment

After assembling of the circuit, adjust TR1 to null value, power-up and make the following adjustments :-

1. Without connecting the battery check that the 2 LED?s are turned on.
2. Connect a car battery to the circuit and check that LD2 is OFF and a current (normally 2A to 4A) is flowing to the battery.
3. Adjust TR1 until LD2 turns ON and the charge current is cut.
4. Adjust TR1 to null value and charge the battery using the hydrometer technique (if you do not have or do not know how to use a hydrometer, then use a good condition battery and charge).

Carefully adjust TR1 so that LD2 begins to turn ON and the charge current falls to a few hundred milliamps (mA). If TR1 is set correctly then in the next round of charging you will noticed LD2 begin to flicker as the battery is being charged. When battery is completely charged, LD2 turns ON completely.TR1 does not need further adjustment anymore. Q1 is connected in line with the battery and is fired by R3, R4 and LD2. The R2, C1, TR1 and D2 sense the voltage of the battery terminal and activate Q2 when the voltage of the battery terminal exceeds the value predetermined by TR1.

When an uncharged battery is connected, the terminal voltage is low. Under this circumstance, Q2 is turned OFF and Q1 is fired in each half cycle by R3, R4 and LD2. The Q1 functions as a simple rectifier and charges the battery. If the battery terminal voltage is increased above the level that had been fixed by TR1, then Q2 shifts the control of Q1 gate. This deactivates Q1 and cuts off the current supply to the battery and turns LD2 ON indicating that the charge has been completed. Q1 and bridge rectifier GR1 should be mounted on heatsinks to prevent overheating. M1 is a 5A DC ammeter to measure the charge current.

Source :users.otenet.gr

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Reuse Old Mobile Phone Battery for LED lighting

Normally mobile batteries have a lifespan of 2-5 years under normal usage. But then we have to replace them. Nowadays there are cheap replacement batteries which cost no more than 1$. But these low cost batteries run only 6-12 months. What to do with the used batteries, which can’t be reused in mobiles? Well, easy solution is to use the batteries in a circuit that requires less current. We can use them for LED lighting.

Do you have old unusable Mobile battery?

Normally mobile batteries have a lifespan of 2-5 years under normal usage. But then we have to replace them. Nowadays there are cheap replacement batteries which cost no more than 1$. But these low cost batteries run only 6-12 months. What to do with the used batteries, which can’t be reused in mobiles?

Well, easy solution is to use the batteries in a circuit that requires less current. We can use them for LED lighting. Thus your automatic lighting emergency light is ready which runs by your waste Mobile Battery.

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Flashing LED Battery status Indicator

Signals when an on-circuit battery is exhausted 5V to 12V working voltage

A Battery-status Indicator circuit will also be useful, mainly to observe portable Test-gear units and equivalent devices. LED D1 flashes to apparel the customers attention, signaling that the circuit is operating, so it's going to no longer be left on by using mistake. The circuit generates about two LED flashes per second, however the mean present drawing might be about 200µA. Transistors Q1 and Q2 are wired as an unusual complementary astable multivibrator: each are off 99% of the time, saturating best when the LED illuminates, in this case contributing to keep very low current consumption. 

Circuit diagram :

Flashing-LED Battery-status Indicator Circuit Diagram

The circuit will work with battery supply voltages within the 5 - 12V vary and the LED flashing will additionally be stopped at the desired battery voltage (comprised within the four.8 - 9V worth) by way of adjusting Trimmer R4. This vary can also be modified via altering R3 and/or R4 worth relatively.

When the battery voltage methods the onerous price, the LED flashing frequency will fall suddenly to alert the consumer. Obviously, when the battery voltage has fallen under this price, the LED will stay completely off. To maintain steady the exhausting voltage price, diode D1 was once brought to compensate Q1 Base-Emitter junction changes in temperature. The use of a Schottky-barrier device (e.g. BAT46, 1N5819 and the like) for D1 is mandatory: the circuit is no longer going to work if a common silicon diode just like the 1N4148 is used as an alternative.

Parts :

R1,R7__________220R  1/4W Resistors
R2_____________120K  1/4W Resistor
R3_______________5K6 1/4W Resistor
R4_______________5K  1/2W Trimmer Cermet or Carbon
R5______________33K  1/4W Resistor
R6_____________680K  1/4W Resistor
R8_____________100K  1/4W Resistor
R9_____________180R  1/4W Resistor
C1,C2____________4µ7  25V Electrolytic Capacitors
D1____________BAT46  100V 150mA Schottky-barrier Diode
D2______________LED  Red 5mm.
Q1____________BC547   four5V 100mA NPN Transistor
Q2____________BC557   45V 100mA PNP Transistor
B1_______________5V to 12V Battery provide
Notes :

• Mean current drawing of the circuit can be lowered further on by using elevating R1, R7 and R9 prices.

Source : Red Circuits

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Low Cost Universal Battery Charger Schematic

Low cost solution for charging of each NiCd and NiMh batteries

Here is the circuit diagram of a low price universal costr for NiCD - NiMH batteries. This circuit is Ideal for automobile use. It has capability to transform a primes adapter in to a costr . This one can be used to cost mobile phone, toys, moveables, video batteries, MP3 gamers, ... and has selectable cost present. An LED is situated in circuit to indicate charging. Can be built on a basic purpose PCB or a veroboard. I hope you in point of fact love it.

Picture of the circuit: 

 A Low Cost Universal Charger Circuit Schematic

Circuit diagram:

A Low Cost Universal Charger Circuit Diagram

Parts:

R1 = 120R-0...5W
R2 = See Diagram
C1 = 220uF-35V
D1 = 1N4007
D2 = 3mm. LED
Q1 = BD135
J1 = DC Input Socket

Specifications:

• Ideal for in car use.
• LED charge indication.
• Selectable cost current.
• Charges Ni Cd or NiMH batteries.
• Transforms a primarys adapter into a costr.
• Charge cellular phone, toys, transportables, video batteries …

Features:

• LED perform indication.
• Power provide polarity protected.
• Supply current: similar as cost current.
• Supply voltage: from 6.5VDC to 21VDC (depending on used battery)
• Charge present (±20%): 50mA, 100mA, 200mA, 300mA, 400mA. (selectable)

Determining the availability voltage:

This desk indicates the minimum and most voltages to supply the charger. See provide voltage choice chart under.

Example:

To cost a 6V battery a minimum supply voltage of 12V is needed, the utmost voltage is then 15V.

Voltage choice:

Voltage Selection Chart For Low Cost Universal Battery Charger

Determining the cost current:

Before constructing the circuit, you have to determinate how a lot present will probably be used to charge the battery or battery pack. It is a good suggestion to cost the battery with a present that is 10 occasions smaller then the battery capability, and to charge it for about 15 hours. If you double the charge current , then that you may charge the battery in half of the time. Charge present selection chart is positioned in diagram.

Example:

A battery pack of 6V / 1000mAh will additionally be charged with 100mA during 15 hours. If you need to charge quicker, then a cost present of 200mA can be utilized for approximately 7 hours.

Caution:

The larger cost present, the extra essential the cost time need to be checked. When faster charging is used, you should discharge the battery totally sooner than charging. Using a cost present of 1/10 of the capacity will increase the lifetime of the battery. The cost time can easily be doubled with out damaging the battery.

Note:

• Mount the transistor in conjunction with the heatsink on the PCB, bend the leads as important. Take care that the metal again of the transistor touches the heatsink. Check that the leads of the transistor don't touch the heatsink.

Source : http://www.ecircuitslab.com

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Battery Charger based on AVR ATMega 8535

Battery Charger in general can be interpreted as a means to recharge the battery charge. Principles of good charger circuit is capable of providing resources to perform effectively charging the battery, efficient and safe. AVR-Based Battery Charger ATMega 8535 With LCD Display This is an idea that had just emerged from the author.

In AVR-Based Battery Charger design ATMega 8535 With LCD Display is using AVR microcontroller processor charger with ATMega 8535, process the data viewer charger with LCD, a safety from a hot temperature with the temperature sensor LM35 and several buttons for setting the charger. And component power charger Battery Charger Based on AVR ATMega 8535 With LCD Display is a FET.

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Function-Based Battery Charger Part Series AVR ATMega 8535 With LCD Display

ATMega 8535 AVR microcontroller serves as the controlling process of the charger.

Button S1 - S5 as input data charger settings (setting the current, maximum temperature, peak voltage batteries)

LM35 Temperature Sensor function as heat sensors in the battery during charge.

LCD Display function to display data and display settings charger battery charger process measurement data.

FET serves as a power charger that will flow into the battery charging current.

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Amplifier audio small to use with 9V battery operated

This is an
audio amplifier that can be used with a small 9 volt Battery
Operated,Current use as little as 5 milliamps.And amplification up to
500 mW.
Which is sufficient to expand the sound from a sound about or the CD Walk Man out to the small speakers clearly.
When entering the power supply 9-volt circuit IC1 number LM386 amplifier IC size is 300-800 mW, Depending on the power supply circuit with,This is from 4-15 volts.


Once entered into the input pin 3,The non inverting pin to amplifier
non-return phase.C1 will be served cut out the noise input to ground.And
C2 increases the rate of amplifier,C2 is to add more value.But if the
C2 Too much distortion (the C2 should not exceed 100uF).The output of
IC1 is out of the pin 5 through C4 coupling audio signals to better and
DC block and not passed to the speaker.For the audio portion will also
be fed back through R2 and C3 to the high frequency response better.
++++++++++++++++++++++++++++++
Next circuit ideals that use LM386 IC.

Amplifier 500 mW with ic LM386N

This
circuit number LM386 IC is used as the IC, which is popular is that it
has. It is a simple circuit. Less equipment items. Suitable for use or
used in small trials.
The properties of the IC can be used from
4V-12V power supply for low current at 50 mA only. And the frequency
response from 40Hz – 100 kHz rate of expansion of 46 dB and distortion.
Less than 1%.


When entering the power supply light LED1 circuit to tell the
operating environment of the circuit. C6 and C7, with a page filter to
smooth then be entered through one input sound signal.
C1 coupling
signal protection dc voltage noise in circuit to the sound signal that
is transmitted through VR1 for controller level reputation of sound
signal and then sent to the input to pin 3 of IC1.
boost up output at
pin 5 through C5 for protection dc voltage and meet the low frequency
better and send out put speakers. The C4 and R1 is acting eliminate
noise signal out and the pin 1 of IC will have a jumper for. to access
the C3 to boost up rate increase in case the circuit to be used to
boost up signal is very small.

Small audio amplifier IC 7w using lm383

This
circuit, will help expand the sound small. such as radio, sound out,
including CD WALKMAN. To the more powerful sound.The amplifier circuit
can be up to 7 watts. Enough to use a good listening room.And most
importantly is a very simple circuit.


Operation of the circuit. be Input signal is coupling with the
C1.Passed into the pin 1 of IC1 number LM383. Amplifier output from
the pin 4.Through C3 increase in low frequency stability better, before
leaving to the speaker. The R2 and R3 set the gain 100 times. Which is
calculated from the (R3/R4) +1.The C2 functions help in frequency
response.

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