Skip to main content
Associate
June 27, 2024
Solved

Pull-up resistor of VL53L5CX

  • June 27, 2024
  • 1 reply
  • 755 views

As shown in the figure, can we change the pull-up resistance of SCL and SDA from 2.2k to 1k?
What is the impact on TOF (VL53L5CX)?

Dust_huan_0-1719455098579.png

 

Best answer by John E KVAM

Yes, you can - and you should - depending on what you are doing. 

Knowing the pull-up on an I2C line is almost an art form. 

Long wires and multiple devices will necessitate changing those pull-ups. 

Philips invented the I2C bus a zillion years ago and NXP bought Philips. 

They have the documentation on how to choose the pull-ups. Or there are lots of web sites. 

I2C pull up resistance, rise time and bus capacitance discussion (fastbitlab.com)

is just one of many you can find. 

This one from TI is good as well:

I2C Bus Pull-Up Resistor Calculation

- john

1 reply

John E KVAM
John E KVAMBest answer
ST Employee
June 27, 2024

Yes, you can - and you should - depending on what you are doing. 

Knowing the pull-up on an I2C line is almost an art form. 

Long wires and multiple devices will necessitate changing those pull-ups. 

Philips invented the I2C bus a zillion years ago and NXP bought Philips. 

They have the documentation on how to choose the pull-ups. Or there are lots of web sites. 

I2C pull up resistance, rise time and bus capacitance discussion (fastbitlab.com)

is just one of many you can find. 

This one from TI is good as well:

I2C Bus Pull-Up Resistor Calculation

- john