FAQ - PLL Synthesizers

AK1574

PLL Synthesizers

[Q0456]
・Can TCXO frequencies other than 50.4MHz be used?
A.
・Can be used. Generally, the higher the frequency, the better the phase noise, and the lower the frequency, the lower Current Consumption.
Was it helpful?
Yes
No
Thank you We will reflect your opinion on the improvement of the web content.
[Q0457]
・What waveforms are assumed by TCXO inputs?
A.
・Assume a typical clipped-sign output TCXO.
Was it helpful?
Yes
No
Thank you We will reflect your opinion on the improvement of the web content.
[Q0458]
・What is the output impedance of the RFOUT_A and RFOUT_B pins?
A.
・Both output impedance of RFOUT_A and RFOUT_B pins are Hi-Z, because these pins  are open-collector. The output impedance depends on an external load resistor connected to the VDD (R9 and R10 of the data sheet P61) and its value is 100Ω (= differential 200Ω) in the data sheet and on the Evaluation Board. To achieve impedance matching in all of the specified wide frequency ranges, the resistor of 100 Ω is used for each.
Was it helpful?
Yes
No
Thank you We will reflect your opinion on the improvement of the web content.