DAC7678: Addressing problem

Part Number: DAC7678

We are using DAC7678 and we have noticed that a very small number of devices with floating address pin initiate with a wrong address when being powered up with a slow ramp rate. Changing the ramp rate is not desirable.

Is there a way of forcing this device to reload it's address after power on?
What is the maximum ramp rate required in order to load the right address?
What is the duration of the internal power on reset signal?

Thanks

4 months ago

0 Paul_Frost 4 months ago

TI__Guru 53173 points

Hi RD,

Please try issuing a software reset after startup to the broadcast address. This should reinitialize all devices even if there are duplicate addresses.

Thanks,

Paul

0 RD 4 months ago in reply to Paul_Frost

Prodigy 10 points

Unfortunately that did not work. The device does not seem to "resample" the address pin after a sw reset.

0 Paul_Frost 3 months ago in reply to RD

TI__Guru 53173 points

How extreme is the supply ramp? Can it be improved by reducing bypass capacitance? You could also consider adding a resistor divider on the address pin of large resistors 500kΩ to 1MΩ. Are you address limited? Can you tie the pin high or low?

Data converters

Data converters forum

DAC7678: Addressing problem