Hi,
I was wondering if anyone is able to supply information of the output mismatch that the MMZ09332B device is able to tolerate without degradation/damage. I am using this as a final output PA stage of a system and this then goes onto an antenna, so i was wondering how poor the match of the antenna could be before i have to worry about damage
Simon
Hello,
It is important to mention that power is reflected whenever there is an impedance mismatch between the transmitter, the feed line, and the antenna (all 50 ohms). If you do not have an antenna connected to the PA probably you have an infinitive impedance.
You can read on this topic here:
https://www.richardsonrfpd.com/docs/rfpd/Freescale-The-Quest-for-a-Rugged-Transistor-Tech-%20Article...
Operation at VSWR=∞ may be risky and should be avoided.
Operation at high VSWR doesn't cause electrical degradation of these devices. However, doing that may cause thermal stress because of excess power dissipated in the device. If all the RF power is reflected back to the device, thermal power increases, and in, the worst case, junction temperature rise and will damage the device.
Hope this helps.
Regards.
OK, Thanks, we've only had one unit so far have failure under adverse output match.
as an aside to this, i have been trying to get hold of an eval board for the MMZ09332B, but it is not anywhere out in the market place, do you know where this could be sourced from that has current stock? or as an alternative can NXP provide ODB++ files and i could look at getting the board manufactured myself