How to connect unused input and output ports such as HMC747, HMC749, HMC746, etc. Is it connected in series with 50 ohms to ground? In other words, how to use a single-ended interface instead of a differential interface?
HMC746
Recommended for New Designs
The HMC746LC3C is an AND/NAND/OR/NOR function designed to support data transmission rates of up to 14 Gbps, and clock frequencies as high as 14 GHz. The...
Datasheet
HMC746 on Analog.com
HMC749
Recommended for New Designs
The HMC749LC3C is a T Flip-Flop w/Reset designed to support clock frequencies as high as 26 GHz. During normal operation, with the reset pin not asserted...
Datasheet
HMC749 on Analog.com
HMC747
Recommended for New Designs
The HMC747 is a D-Type Flip-Flop designed to support data transmission rates of up to 13 Gbps, and clock frequencies as high as 13 GHz. During normal operation...
Datasheet
HMC747 on Analog.com
How to connect unused input and output ports such as HMC747, HMC749, HMC746, etc. Is it connected in series with 50 ohms to ground? In other words, how to use a single-ended interface instead of a differential interface?
Unused inputs should be terminated with a similar network with the used inputs. If used ports are AC coupled, then unused ports can be terminated to gnd with DC block cap and 50 ohms. If the used port is DC coupled, then the unused port should be terminated to the high supply rail of the part(GND for parts having -3.3V, Vcc for parts having +3.3V)
Is it directly connected to the high power rail? No need to connect a 50 ohm resistor between the unused interface and the high power rail