T
treez
Guest
Hi,
We have a DALI comms based LED driver. This contains the LED driver and the DALI power supply (this is just a 16V rail with a current clamp on it). However, sometimes, our customers will connect their own 16V DALI rail into a DALI power supply connector…as shown in the schematic. Sometimes, the production staff may accidentally connect the 16V DALI rail in the wrong way round , (as shown in the schem).
Therefore, we have added diodes D1, D2 and D3 to protect against reverse polarity connection. Part of this is to prevent the NPN BE junctions getting too far reverse biased by a reverse polarity connection.
We cant just use a reverse polarity diode near the connector, because sometimes there is no external DALI power supply, and sometimes the internal DALI rail needs to go to the outside via the connector.
Do you think there is a more efficient way to provide the reverse polarity protection here…instead of using three diodes like we have?
LTspice sim also attached
We have a DALI comms based LED driver. This contains the LED driver and the DALI power supply (this is just a 16V rail with a current clamp on it). However, sometimes, our customers will connect their own 16V DALI rail into a DALI power supply connector…as shown in the schematic. Sometimes, the production staff may accidentally connect the 16V DALI rail in the wrong way round , (as shown in the schem).
Therefore, we have added diodes D1, D2 and D3 to protect against reverse polarity connection. Part of this is to prevent the NPN BE junctions getting too far reverse biased by a reverse polarity connection.
We cant just use a reverse polarity diode near the connector, because sometimes there is no external DALI power supply, and sometimes the internal DALI rail needs to go to the outside via the connector.
Do you think there is a more efficient way to provide the reverse polarity protection here…instead of using three diodes like we have?
LTspice sim also attached