RF passive components?

[ravenfeather]

Hi
I want to know what kind of capacitors and resistors ( the material) are used in high frequency applications like ZigBee or in the 900Mhz band?

[mylogin]

900MHz to 2.4GHz you can use the regular chip resistor, capacitor, 0804, 0r 0603 size. 

[ravenfeather]

Thank you for the reply.And what you think is easier to implement ZigBee ( the chip is impossible to solder fot me QFN ) or Rf at 900 Mhz ( more passive components around)?I'm not good with controllers either, but people are alwas impatient

[Kwaigo]

Some types of chip resistors (even 0603 and 0402) have thick film layer, so their resistance at high RF may be differ because skin effect. 0805 chips (capacitors) too large for 2.4GHz. Use 0603 or smaller.

[mylogin]

the important thing is keep the distance short (such as bypass capacitors) and the PCB trace impedance, try to match the size of components with the PCB trace width,  do not use too small component with wide PCB trace, it will create discontinues.     the thin film resistor is expensive, and for 10% tolerance it is not necessary.

[strabush]

For rf circuits use only NPO type capacitor, they are stable and linear.