LP5562 / I2C problem

K.Yaita

Other Parts Discussed in Thread: LP5562

Hi Team,

My customer uses LP5562 and I heard he has a I2C problem in his system.
He said any of I2C slave device holds SDA line "Low" and it can't be released even if more than nine clock pulses are sent from I2C master.
I would like to ask if LP5562 could hold SDA line "Low" during many clock pulses.

I believe LP5562 couldn't but would like to confirm just in case.

Best regards,
Yaita / Japan disty

over 9 years ago

0 Hak-Leong Ng over 9 years ago

TI__Intellectual 1985 points

Hi Yaita,

As far as I know, I have not come across a case where LP5562 will hold SDA line LOW during read operation. Is the customer facing this problem right now? Is LP5562 the only device on that I2C bus? If the customer can provide more details on how this happen, I can try to duplicate this on our EVM.

Regards
H L

0 K.Yaita over 9 years ago in reply to Hak-Leong Ng

Guru 29720 points

Hi Hak-san,

I appreciate for your support.

>Is the customer facing this problem right now?
Yes, my customer is facing this problem right now..
There is another slave devices on that I2C bus, however it seems the problem is occured when VCC/EN pin of LP5562 is dynamically enabled/disabled.
I updated this issue to the following thread.
https://e2e.ti.com/support/power_management/led_driver/f/192/t/521967

Please see above and it would be really appreciated if you give me your comment.

Best Regards,
Yaita

0 Hak-Leong Ng over 9 years ago in reply to K.Yaita

TI__Intellectual 1985 points

Hi Yaita,

Yes, I remember your question about having VCC/EN set to 0V, this should not damage LP5562. So what you are saying is that I2C bus stops working when VCC/EN pin of LP5562 is set to 0V and back to 3.3V? or it works when VCC/EN is at 3.3V and stops working when VCC/EN is at 0V?

Regards
H L

0 Hak-Leong Ng over 9 years ago in reply to Hak-Leong Ng

TI__Intellectual 1985 points

Hi Yaita,

I will continue the rest of the discussion in the other thread

e2e.ti.com/.../521967

Regards
H L

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LP5562 / I2C problem