I have customized my own PN532 board.
1. For first assembly the board was working some time and some time it did not.(was getting i2c address , card read some time and other time it did not read the i2c address).without ground tap in antenna
2. Second time same board i assembled i am able to read i2c every time. but it is not able to read any card.
i tried nfc energy harvesting ic so without ground tap on antenna it showed no power, led glowed very less. then i ground tapped antenna so i was able to get full glow on LED on board energy harvesting ic. but still not able to read cards.
attaching the Schematic and board image