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Hello AB, To get the higher output power on ADL5375, we need to feed the bigger baseband ac signals and at the same time that also should be at 0.5V dc biased for ADL5375-05. Let's think the interface without a filter since that filter is designed at 100ohm differential input/output impedance and will think to change component value. RSLI/RSLQ on Figure 4 in CN0205 is ac-limiting resistor. and we can get the higher output power with the higher value there. If taking 100 ohm out, it becomes 2Vp_p differential baseband input signal level(with same 20mA full-scale current and 50 ohm termination resistors) and we can get 6dB higher output power(6~7dBm Pout). It keeps 0.5V dc bias level on I/Q inputs. Please check output power with a power calculator tool from attached link.(Figure 11 on CN-0205). http://www.analog.com/CN0205-PowerCalculator You can increase DAC output signal level by increasing full scale current or increasing termination resistors( RBIP,RBIN,RBQP,RBQN). But there would be dc common mode voltage change accordingly. So we need a level shifter additionally to meet the 0.5V requirement . And also need to consider the compliance voltage on AD9122. there would be limitation and performance degradation. You may need to check this with a AD9122 supporting team. You can see the performance(Pout,others) vs Baseband input signal level on Figure 38~Figure40 on datasheet. Thanks Tony