Part Number: LMX2594
Hi team. What is the residual power at Output A and Output B in POWER DOWN mode (R44 or R44 is set to 0) reference to maximum output level? The most interest for me is the next combination: Output A in active mode and Output B in PD mode (R44=1, R44=0). What is the residual power at Output B in this case? Is it like Xtalk=-50 dBc (table 6.5 of datasheet)? How it will be changed if at the same time power down external Vcc pullup at Output B?
When the buffer is powerdown, the output signal is around -4x dBm.
If you only need one output buffer, you can leave the pins of the unused buffer open. The buffer is an open-drain buffer, without the external pull-up, it should not working and I believe the output signal will be less than -4x dBm.
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In reply to Noel Fung:
Noel, thank you for your answer. In my application I need both outputs: Output A is always on and Output B some time turn on and some time turn off. The level of an Output B Power Down state is critical for me. Can you measure a real level of an Output B Power Down state for frequency band 10 - 15 GHz?
In reply to Pavel Pershin:
We will take some data tomorrow. Stay tuned.
I tested this in the lab on the EVM, for 14 GHz VCO, OUTA_MUX = VCO, OUTB_MUX = VCO
I briefly checked at 12 GHz and 10 GHz and saw that the case where both outputs were turned off resulted in much lower power in the -40 dBm to -50 dBm range. There wasn't a significant difference in the one output powered down case.
In reply to Vibhu Vanjari:
Noel, Vibhu. Big thanks for your answers.
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