Hi Guofred,
See please my answers below.
i don't have found some parameters about S32K3+FS26,the details as below.
1) supply voltage: 2.97~5.5 V(from the S32K3 datasheet)
issue1: requirement 2.7~3.6 V, 2.7<2.97, the S32K322 can be normal work or not if we set the supply voltage is 2.7
[Lukas] S32K3 has low voltage detectors which will force the device to reset state if the voltage is not sufficient. There’s a note in the datasheet:
“Device functionality is guaranteed down to the LVR assert level, however electrical performance of 12-bit ADC, CMP with 8-bit DAC, IO electrical characteristics, and communication modules electrical characteristics will be degraded when voltage drops below 2.97 V.”
So, if the voltage falls down, first the S32K3 will assert reset (typical value is 2.85V as shown in the DS) and then, little bit later, FS26 will react in addition. So, I can see no problem here.
2) what is the system clock precision on the S32K322.
issue: requirement: ±1S/24H，it can be meet this requirement or not.
[Lukas] If you want to achieve high accuracy, it’s necessary to use external oscillator, not FIRC/SIRC. So, the accuracy is then given by your external oscillator, not by the MCU.
3) what is the quiescent current on the S32K322.
issue: requirement: Pin less than 500uA for low power consumption. it's ok to meet or not.
[Lukas] Some data are already available in the datasheet, Table14:
https://www.nxp.com/webapp/Download?colCode=S32K3xxDS
The characterization is still ongoing, more details will be available in next revision of the datasheet. Probably in Q1/2022.
4) the hardware of the reset circuit, it needs to add the external chip to finish reset circuit or not.
[Lukas] External pull up resistor is sufficient. More details can be found in Hardware Design Guidelines in “an679302 - S32K3 - Hardware Design Package_Rev_A (0.2)” which can be found on the DocStore (docstore.nxp.com).
5) it can be normal work less than 200ms during the power-on start up time. is it correct ?
SBC need to get watchdog signal, i remember finish doing normal feed dog <=256ms,the MCU can be normal work. if we requirement this time is less 200ms, the MCU meets this requirement or not.
[Lukas] Yes, boot time is faster. See please section “6.4 Power mode transition operating behaviors” in the datasheet.
Regards,
Lukas
