RF transistor output impedance
时间:04-07
整理:3721RD
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Hi,
ADS Load pull test for PD20015 gives 0.389+j*0.085 which is obtained by placing marker m3 as shown in the figure. My question is that , to which impedance does it point. is it transistors (looking into the device) impedance or the load impedance (looking outside the device output)?
ADS Load pull test for PD20015 gives 0.389+j*0.085 which is obtained by placing marker m3 as shown in the figure. My question is that , to which impedance does it point. is it transistors (looking into the device) impedance or the load impedance (looking outside the device output)?
This is load impedance that should be seen by the transistor.
Thanks for reply.
It means that, load impedance "0.389+j*0.085" should be transformed to 50ohm.
Can i ignore imaginary part of impedance at 1800MHz and match only real part.
You should match to both, but it might not matter too much for you since the imaginary part is much smaller than the real part.
But that impedance seems awfully small. I usually expect the magnitude to be at least 10ohms or so.
