Linux/AM3358: RTC continuous update

MADHU GANDEPALLI

Expert 1300 points

Part Number: AM3358

Tool/software: Linux

Hello

I have designed a custom board of AM3358 with reference as General purpose EVM.

In my design I have used a battery coin of 3.3 V and given to VDDRTC . So my RTC is ON continuously.

But every time i power-on my board RTC value is not upgrading. Kindly help me what all the things I still need to do to get my RTC updated continuously even though my board is powered off.

Regards

Mad_hu

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

Please post the RTC related part of your schematic. VDDS_RTC is a 1.8V power supply and cannot be powered directly from 3.3V source. This will damage the processor.

0 MADHU GANDEPALLI over 7 years ago in reply to Biser Gatchev-XID

Expert 1300 points

Hello Biser

The following is the schematic you wanted.

Regards

Mad_hu

0 Biser Gatchev-XID over 7 years ago in reply to MADHU GANDEPALLI

TI__Guru**** 393215 points

This seems OK. Now, are you using the AM335x internal RTC? Do you have a 32kHz crystal connected on OSC1? What PMIC are you using?

0 MADHU GANDEPALLI over 7 years ago

Expert 1300 points

Part Number: AM3358

Tool/software: Linux

Hello Biser ,

Sorry for the late reply.

We have an oscillator connrcted to the OSC1 and also we are not using PMIC of TI

Regards

Mad_hu

0 Biser Gatchev-XID over 7 years ago in reply to MADHU GANDEPALLI

TI__Guru**** 393215 points

You should check your power switching circuit to the LDO. There may be glitches when power is being switched, causing the RTC power to drop.

Processors

Processors forum

Linux/AM3358: RTC continuous update