Tx Analog in Settings

Hi All,
I’m trying to connect signal generator to Myriad RF board Analog input ports. What is the common mode voltage and voltage swing to drive them?

Hi andrelEe,

LMS6002D Analog inputs require a 0.6V common mode offset voltage with a 300 mVp-p voltage swing for optimum performance.


Hi Andrew,
As per LMS6002D datasheet. Analog Tx IQ input signal specification are 250mVpp and common mode voltage of 65mV. Please refer to Table2: General RF specification section of the DS. This is different from what you have mentioned in your reply. Could you please confirm the Tx IQ input signal specification ?

Thanks and Regards,
Subrahmanya K S

Literally it is the same. CM 650mV and 250mVpp gives the same peak value as CM 600mV with 300mVpp. In this case you SNR would be better.


Is the common mode voltage is 600mV or 65mV ? As per LMS6002D datasheet it is 65mV where as Andrew mail and Zipper Development Kit_1 0r5.pdf section #7.1.1 it is mentioned as 600mV. is This a typo in the datasheet ?

Subrahmanya K S

Most likely it is a typo mistake


For providing external I Q signals for TX what should be the settings of “DAC Internal Output Load Resistor” for optimal performance of Tx path ?

what will be the input resistance of TXINI and TXINQ pins when “DAC Internal Output Load Resistor” = “open circuit” ?

Subrahmanya K S

When you use external signals for TX path, power down the DACs.
You can program the input impedance using “DAC Internal Output Load Resistor” register. I Open state the impedance is high ohmic, recommended value is 200 Ohm