What Must todo

This universal battery charger is based on LM317 and has an adjustable regulated output voltage and also has an adjustable constant-current charging circuit that makes it suitable to use for charging most NiCad batteries and some other types of batteries . This LM317 universal battery charger can charge a single cell or a number of series-connected cells up to a maximum voltage of 18 V.

This universal battery charger circuit use just some common electronic components like LM317 regulator , operational amplifier and some 2n3055 power transistors .2n3055 power transistors Q1 and Q2 are connected as series regulators to control the battery chargers out¬put voltage and charge-current rate. The LM317 used as an adjustable voltage regulator supplies the drive signal to the bases of power transistors Q1 and Q2.



By turning the potentiometer R9 the output-voltage level will be modified. A current-sampling resistor, R8 (a 0.1-fi, 5-W unit), connected between the negative output lead and circuit ground.As the charging voltage across the battery begins to drop, the current through R8 decreases , then the voltage feeding pin 5 of U3 decreases, and the comparator output follows, turning Q3 back off, which completes the signals circular path to regulate the batterys charging current. The charging current can be set by adjusting R10 for the desired current.

The schematic above can be used for supply on color TV for all type TV circuit. But we need to know how much voltage needed by the circuit of color Television. To set the output voltage, the setting on VR1 1K ohm. Required input voltage 300V DC which is already on TV circuit, so we just take a 300V dc voltage existing on the TV circuit, and for a circuit supply voltage on our TV cut the line PCB and connected with this  universal switching power supply.For the transformer we can use the TV regulator transformer.

Part List :

• R1 = 33R 5W
• R2 = 330R 1W
• R3 = 2K2
• R4 = 47K
• R5 = 2K7
• R6 = 22K
• R7 = 390K
• R8 = 47R 1W

• C1 = 100uF 25V
• C2 = 1n2 2KV
• C3 = 18n
• C4 = 18n

• D1 = 1N4148
• D2 = 1N4148
• D3 = ZD 12V
• D4 = 1N4007
• D5 = 1N4007

• VR1 = 1K
• ZD1 = Zener 6V
• T1    = TV regulator transformer
• Q1   = K2847
• Q2   = C2328A

In this post I will share about using Accu source to charge batteries that can be used on any mobile brand, or can be called universal phone battery charger. Because the battery charger using a source of 12V, the charge accumulator can also be used in cars and others.

This will out charger circuit voltage of 5 volts DC, with input from at least 6 volt battery, and voltage inputs that have been tried till with 15 volts (more than it has not been tried, because the battery that tie the maximum output voltage is only 13.8 volts).