Here a simple homemade emergency light using two power LEDs. The assembled picture of the circuit is shown in figure 1 and figure 2. The circuit is assembled on the PCB and mounted over the battery, so as to fix simply and also to be used as a torch.
The circuit of the Led driver for emergency light is shown in the circuit below.
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| Emergency light fig-1 |
The circuit of the Led driver for emergency light is shown in the circuit below.
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| Power LED emergency light circuit diagram |
As shown in the circuit a charging voltage of 4V is applied to the circuit, the battery used is a 4V 1.5AH lead acid battery. The led D4 is connected for to indicate the charging supply is ON, thus to identify whether the battery is charging or not. The diode D3 is to prevent the backward flow or to prevent reverse of polarity of charging terminals and also to prevent the led ONs during no charging . The diode D1 and D2 are two power LEDs of 1watts power rating, which is controlled by an SPST switch S1.
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| Emergency light fig-2 |
Components required
Resistor
R1 - 100
Diode
D1,D2 - 1w power LED
Resistor
R1 - 100
Diode
D1,D2 - 1w power LED
D3 - 1N4007
D4 - Green LED
Switch
S1- SPST
Battery - 4V, 1.5AH Lead acid battery
