In our system, the Dialog DA14581 chip is powered down most of the time. Periodically it is powered up by a separate ASIC to advertise and possibly connect with a master device. There are also cases in which the Dialog chip is powered down and then immediately powered back up again.
For this particular case, a Dialog Field Application Engineer (FAE) recommended that our ASIC always assert the Dialog chip reset pin to perform a chip reset immediately after every power up since the chip may be left in an indeterminate state if powered up immediately after being powered down.
Given this recommendation, would it be equivalent to assert the Dialog chip reset line at power up, and then release it a few milliseconds later? This approach is simpler and quicker.
Thanks,
Jim
Hi James Hiebert,
I am not sure i understand the question, the recommendation of the FAE was to issue a reset via asserting the reset line of the SoC after powering up the device, your question is about the timing of asserting the reset line ? If it has a difference to have the reset asserted while powering up or assert the reset right after power up ? Is this the question ? I suppose that results would be the same having the reset asserted after powering up the device or having the reset line asserted while power up and then release the reset signal.
Thanks MT_dialog
MT,
Sorry for the confusion!
The FAE recommended asserting the reset pin of the DA14581 immediately after power up, in case the DA14581 had been powered down only a very short amount of time. So:
1. DA14581 is powered
2. DA14581 power withdrawn
3. DA14581 immediately powered up
4. Assert reset pin after a short delay
5. De-assert reset pin at least 2us later
With this approach defined above, there are actually 2 resets: one when power is re-applied and the second when the reset pin is de-asserted. We would like to eliminate the second reset.
I am wondering if this approach is equivalent:
1. DA14581 is powered
2. DA14581 power withdrawn
3. DA14581 immediately powered up and reset pin asserted simultaneously
4. De-assert reset pin after at least 2 us
Thanks,
Jim
Hi Jim,
Yes, i suppose that will be equivalent and will save you an extra reset.
Thanks MT_dialog
Thanks!