S9KEAZ64AMLH Power On Issue

[dannydeng]

Dears,

  I get stuck on S9KEAZ64AMLH Power On testing, when testing start, voltage on Vcc Pin is rising 100mV evry 1 minutes until 5.8V. However when we run customer's application in this testing, the board would stick every time.

  Can you help to advice?

BRs,

Ray

[jingpan]

Hi,

S9KEA won't lift input voltage. The operation voltage of S9KEA is 2.7v~5.5V. Although in datasheet table 1, it shows the maximum VDD is 6v, absolute maximum ratings are stress ratings only, and functional operation at the maxima is not guaranteed.

Please check the power supply and try to keep the voltage under 5.5v first.

Regards,

Jing

[dannydeng]

Hi Jing,

Thanks for your kindly help,

In this testing, customer have 3 cycles.

1. Rising voltage from 0 to VCC(monited is 5.2 Max) and then drop to 0 in 5 minutes,

2. Rising voltage from 0 to VCC(monited is 5.2 Max) and then drop to 0 in 25 minutes,

3. Rising voltage from 0 to VCC(monited is 5.2 Max) and then drop to 0 in 60 minutes,

  Only in the 3rd cycles, we can not find the MCU work normally, would you please kindly help to advice?

BRs,

Ray

[jingpan]

Hi,

there is no report say KEA can't power up too slow. It only can't ramp up too fast. So, I think there must has some hardware or software problem.

1.Can you share the schematic and software setting?

2. Please observe Reset_b pin status when mcu fail.

This is the KEA power on sequence

KE/KEA POR Sequence and ICS Module Investigation 

Some check points

https://community.nxp.com/message/1089668?commentID=1089668#comment-1089668 

Regards,

jing

[dannydeng]

Hi Jing,

   Tested again, and found when voltage reach 2.7V DC with Power on slowly, I can attach the Multilink to the MCU, software runing regularly, but found the PWM output with many noise and wrong duty,

BRs,

Ray

[jingpan]

Hi,

S9KEA Voltage range is 2.7 to 5.5 V. If voltage stay in this value, slight voltage fluctuate will cause LVD(low voltage detect) to trig interrupt or reset.

Regards,

Jing