cupoftea
Advanced Member level 5
Hi
The DALI signalling system seems very odd. I mean, each DALI device is connected to the DALI bus via its current limited source…..this being needed so it can pull the bus up…..but then if one device needs to pull the DALI bus low, and there are, say, 250 devices on that DALI bus, then that DALI transmitter needs to pull down over an Amp of current!......this is a very poor system. You end up with signalling transistors being heatsinked TO220’s!
Why is DALI so odd?
And surely there needs to be a rule that if a device is not transmitting, then it should turn off its current source, so that any device that needs to pull the bus low doesn’t have to pull so much current.
We are seeing DALI transmitters with multiple channels of DPAK FETs….all heatsinked!......
The DALI signalling system seems very odd. I mean, each DALI device is connected to the DALI bus via its current limited source…..this being needed so it can pull the bus up…..but then if one device needs to pull the DALI bus low, and there are, say, 250 devices on that DALI bus, then that DALI transmitter needs to pull down over an Amp of current!......this is a very poor system. You end up with signalling transistors being heatsinked TO220’s!
Why is DALI so odd?
And surely there needs to be a rule that if a device is not transmitting, then it should turn off its current source, so that any device that needs to pull the bus low doesn’t have to pull so much current.
We are seeing DALI transmitters with multiple channels of DPAK FETs….all heatsinked!......