LP5018: Unable write the reg.

Hi Patel,

Please help to capture the waveform of below 3 items:

1. VCC input voltage waveform;

2. VCAP output voltage waveform;

3.I2C interface waveform.

Thanks!

BR, Jared

Hi BR Jared,

Thanks for your quick responce .... I have atteched here all 3 waveforms. 
I have also atteched schematics for review.

Please check and give some valueable input on this.

Thanks !!!

Hi Patel,

I think the schematic has no problem.

For your waveform, I think it's kind of strange.

• SCL: I am not sure if the high level can sample the correct data for SDA since it seems quite short. But based on our spec, the minimum CLK high time is 600ns. Please have a check.
• SDA: The waveform shows me total 9 bit data, I think it should be 8 bit slave address and 1 bit ACK signal. I am wondering that if it has ACK data, it means that the device received it. But why is there any other data behind it.

BR, Jared

Hi Jared,

Thank you for review the schematics and making the point clear. 

• SCL: I have checked it at multiple clock frequencies, ranging from 100 kHz to 400 kHz, and measured the values. It meets the requirements mentioned in the datasheet (Clock Low time > 1.3 µs and Clock High time > 600 ns).

• SDA: I am also unsure why there is a small spike right after the ACK bit.

  I have atteched here timeing waveform for SDA and SCL. The left one when I try to write 0x40 at 0x00 reg. for enable the chip and right one for just checking I2C Bus status. 
  
  

  

Thank you !!

Hi Patel,

Glad to hear you! It seems that the I2C write is worked.

For the small spike, the reason is that the device will response to host if it received the command.

Please free to contact me if you have any questions!

BR, Jared

Hi Jared,

Still my issue is not resolved. Still unable to write any value in reg.

Do you have any example code for this IC(LP5018)??

Hi,

Sorry for the late reply due to the New Year Holiday. Our expert will reply you today.

Hi Patel,

Sorry about my misunderstanding, please tell me your email address, I will help to send you the sample code for LP5018.

BR, Jared

Hi Jared, 

Thanks for your responce and sorry for the late reply. 

Here is my Email address: amarjeet.kumar@vvdntech.in

Thank you!

Hi, Amarjeet

Jared will send you the email late.

Hi Zhiqian Wu and Jared,

Thanks