MC33771C sleep Mode

[prabhus]

 MC33771C IC, issue with the OV and UV fault triggering when it's in sleep mode.

In normal mode, everything seems to be working fine, but once it goes into sleep mode, the OV and UV faults don't get triggered as expected.

 if there are any specific settings or configurations that need to be adjusted for the IC to properly detect OV and UV faults in sleep mode? Sometimes different modes can have different requirements.

[prabhus]

Hi Jozef,

Now its working fine thank you so much...during sleep mode What about VCOM  LED status? i put cyclic timer 8sec. LED Continuous glowing,after went to sleep mode also.

Regards,

Prabu.S

[JozefKozon]

Hi Prabu,

please share the EVB number you are using. I have checked RD33771CDSTEVB user guide, and the VCOM LED should be on when the the MC33771C is in Normal mode. Not stated VCOM LED behavior in Sleep mode. 

With Best Regards,

Jozef

[prabhus]

AFE Development Board FRDMC33771CSPEVB

[JozefKozon]

Dear Prabu,

according to the UM11402 the VCOM LED indicates normal mode or low power mode. According to the MC33771C datasheet, the low power state is different, than Sleep mode. It looks your board works correctly.

With Best Regards,

Jozef

[JozefKozon]

Dear Prabu,

if the OV, UV is working in normal mode, it should be also working in sleep mode. No changes are needed. Please refer to the Table 38. in the MC33771C datasheet.

Please check how you have set the CYCLIC_TIMER bit in the SYS_CFG1 register. 

In SLEEP mode, the overvoltage, undervoltage, overtemperature, undertemperature, and overcurrent circuitry can remain cyclically active, as well as the monitoring of VPWR.

The cyclic measurement is disabled by default. Cyclic measurement can be activated by writing to
SYS_CFG1[CYCLIC_TIMER].

With Best Regards,

Jozef