Author Topic: NHD-C0220BiZ-FS(RGB)-FBW-3VM I2C Help  (Read 368 times)


  • Newbie
  • *
  • Posts: 1
  • Karma: 0
    • View Profile
« on: March 18, 2019, 03:13:58 PM »
Hello all,

I am using a NHD-C0220BiZ-FS(RGB)-FBW-3VM with I2C functionality. I have been able to get this LCD working before but now I am having troubles with SDA and SCK. I have tried multiple different resistances and multiple addresses. I am using the address of 0b01111000 (0x78) and have tried multiple resistances on the pull up lines. If the resistance is too high, the SDA and SCK lines will drop to 1.5V. If the resistance is about 1K the lines are able to send data from my controller, but I believe the LCD cannot pull the line low to acknowledge the command. It seems like the LCD is drawing a lot of current on the SDA and SCL lines. Is this a thing?

Thanks in advance!


  • Administrator
  • Full Member
  • *****
  • Posts: 118
  • Karma: 4
    • View Profile
Re: NHD-C0220BiZ-FS(RGB)-FBW-3VM I2C Help
« Reply #1 on: March 20, 2019, 08:51:39 AM »
Hi kharding,

Please check and confirm the "L" level input is less than 0.8V and the "H" level input is more than 2.31V to be withing the specification. 
It may also be good to check the noise level on the source waveform using a scope as this may affect the logic level transitions.

Best Regards,


NHD‐C0220BiZ‐FS(RGB)‐FBW‐3VM capacitor on pin 7&8

Started by Ticoti0xFFBoard Character LCDs

Replies: 1
Views: 5560
Last post April 09, 2014, 10:17:30 AM
by Michael_L
NHD‐C0220BiZ‐FS(RGB)‐FBW‐3VM Potting

Started by SebKisterBoard Character LCDs

Replies: 1
Views: 4553
Last post June 22, 2016, 04:51:17 PM
by Saurabh_B
Blank Display on NHD‐C0220BiZ‐FS(RGB)‐FBW‐3VM

Started by SteveCBoard Character LCDs

Replies: 3
Views: 10348
Last post May 13, 2014, 12:04:36 AM
by SteveC
NHD‐C0220BiZ‐FS(RGB)‐FBW‐3VM - Cable for LED Backlights

Started by wadehBoard Character LCDs

Replies: 2
Views: 3614
Last post December 02, 2016, 06:02:27 PM
by wadeh
Sample Code Question for NHD‐C0220BiZ‐FS(RGB)‐FBW‐3VM LCD

Started by SteveCBoard Character LCDs

Replies: 2
Views: 7002
Last post July 31, 2014, 08:44:29 PM
by SteveC