this circuit is the first part for an emergency lamp circuit, it charge the batteries while the power is on and light the led when the power is off
i can not understand how it works?
can anyone help??

 

It is a transformerless power supply.
The diodes rectify the current to one polarity.
The 2.2 uf capacitor limits current into the diode bridge.

 

It is a transformerless power supply.
The diodes rectify the current to one polarity.
The 2.2 uf capacitor limits current into the diode bridge.

dear friend
my problem is that i do not know how to analyse it

 

Do you understand how a 4 diode bridge rectifier AC into pulses of DC?
The only change here is a capacitor is limiting the AC current instead of a resistance or an inductance of a transformer.

 

Do you understand how a 4 diode bridge rectifier AC into pulses of DC?
The only change here is a capacitor is limiting the AC current instead of a resistance or an inductance of a transformer.

yes,i do
i think that there is a mistake in the circuit
the bridge is not connected properly!!?

 

The bridge is drawn correctly.

The 100 uf capacitor is where the load, or battery would be.

One diode junction is grounded and the other is giving out only positive peaked pulses of DC current.

There is no mistake in the diagram.

 

D3 is drawn the wrong way round.

 

D3 is drawn the wrong way round.

Agree.

 

The discussion of this kind of circuit is not permitted out of concern for the safety of people who might attempt to built it.

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