yaly
Newbie level 3
hello everyone,
I'm a newer to IC design and this is my first topic here.
I designed a PLL ,and in the simualtion separate ground and power (say gnd2 /vdd2) are used for VCO and chargepump in order to minimize the noise from digital citcuit such as PFD and divider.When i do the layout,many Psub pickups are used beside the VCO devices for perfect grounded,and they are connected to gnd2 line. However ,the gnd line ( the ground line of digitsl parts) is also connect to sunstrate. Does that mean gnd and gnd2 are connected together? How can i do my layout to achieve a "real" separate gnd2?
Thanks for any insights!
I'm a newer to IC design and this is my first topic here.
I designed a PLL ,and in the simualtion separate ground and power (say gnd2 /vdd2) are used for VCO and chargepump in order to minimize the noise from digital citcuit such as PFD and divider.When i do the layout,many Psub pickups are used beside the VCO devices for perfect grounded,and they are connected to gnd2 line. However ,the gnd line ( the ground line of digitsl parts) is also connect to sunstrate. Does that mean gnd and gnd2 are connected together? How can i do my layout to achieve a "real" separate gnd2?
Thanks for any insights!