SN65LVDS93B: inquire about data input pullup

Part Number: SN65LVDS93B
Other Parts Discussed in Thread: SN75LVDS83B

Hi TI experts,

We review SN65LVDS93B and SN75LVDS83B as a RGB to LVDS converter IC. 

SN65LVDS93B and SN75LVDS83B datasheet application schematic(10.2) have pull-up resistors in data line. However, there is no pull-up resistor in the EVM schematic.

Question 1 : Could you tell us Why is there no pull-up in the EVM circuit?

Question 2 : Must need pull up resistor in data input line?

Thank you.

Downey Kim.

  • Hi Downey,

    I will look into this and get back to you by the end of the week. 

    Best,

    Shu

  • Hi Downey, 

    The datasheet specifies that the data inputs accept 1.8V or 3.3V as the input voltage. That is the case for the EVM circuit.

    In the example schematic in the datasheet, the IOVCC source is shown 1.8V, 2.5V or 3.3V. I am suspecting the pull-up resistors are there to accommodate for the voltage should it not be the accepted input voltage of 1.8V or 3.3V. 

    I believe as long as you have the correct input voltages to the data inputs (1.8V or 3.3V), no pull-ups are needed. 

    Best,

    Shu