• Resolved

Frequency response of 0 ohm resistor on 50-ohm line?

Hi:

Application Note AN098 (Layout Review Techniques for Low Power RF Designs) recommends using a 0-ohm resistors in series for un-mounted components in a pi filter for antenna matching.

Some 0-ohm resistors have a very poor frequency response. My design operates on the 433 MHz UHF band. What resistor/jumper technology would be the best for this type of jumper? I'm considering solid copper strips and metal based sensing resistors (at around 1-5 miliohm).

Thanks.

  • Guru 140995 points

    We have never seen this as an issue. A 0 ohm resistor contribute about 0.3 nH. We use resistors from Vishay at the moment. 

    In other words I don't see any reason for using something different from a 0 ohm resistor. 

  • In reply to TER:

    Thanks. Would you mind sharing the series of Vishay resistors? I've considered WSL series (WSL060300000ZEA9), which are solid copper strips (as opposed to thick or thin film) but I can't find in stock anywhere. Maybe the PZHT (thin film) or the RCWP (thick film) would do it?
    I'm also considering metal-foil from other manufacturers.
  • Guru 140995 points

    In reply to Carlos Lopez4:

    I don't have them in front of me but most of our reference designs uses a 0 ohm resistor. Check the CC1310 reference designs and the BOM excel file for details.
  • In reply to TER:

    Thanks! That will be very helpful.