EEVblog #811 - How The Varta 15 Minute Battery Charger Works

[Mr Smiley]

Hi All,

I had a few VANSON 1 hour chargers. The first one failed by cooking the battery in the first slot. Then the second one started to do the same, again in the first slot. I tried drawing out the circuit and was as confused as Dave was at the beginning.

I did eventually find a schematic for a VARSON V6000, which was a re-branded version of the one's I had. It was multiplexed in operation.

Not quite the same as this VARTA, the fets are transistor driven and there's no discharge function but I've added the schematic for you to see.

Might put some insight on how the VARTA works