The voltage across Lgnd, Vlg, is referred to as ground bounce
As noise margins shrink and it gets harder to reduce other items in the noise budget, such as switching noise, rail collapse and ground bounce
, designers will be looking at the low-hanging fruit to squeeze out the last millivolt of noise.
is voltage created between two different points on the ground return path.
causes unwanted noise in the system and is more prominent with faster switching devices, or when there are more voltage swings (CMOS devices).
Decoupling capacitors are placed between the device and the stray inductance that can contribute to ground bounce
is a transient voltage generated between two different points on the same ground path, such as a package lead, a connector pin or different locations on the ground plane of a circuit board.
The devices' latch-up immunity provides superior resistance to the ground bounce
and negative input transients that cause false triggering in noisy environments.
1 software allows FPGA designers to analyze and optimize I/O pin placement and output switching characteristics to minimize undesirable noise and ground bounce
on a PCB.
SIwave's full-wave, finite-element technique allows designers to characterize simultaneous switching noise (SSN), inter-symbol interference (ISI), power and ground bounce
, resonances, reflections and coupling between traces and power/ground planes across the package and through the board.
By identifying the precise locations of design weaknesses and their impact on dynamic voltage drop and ground bounce
, RedHawk-EV allows designers to not only verify potential power-related functional and timing behavior, but also avoid excessive over-design.
These models can be subsequently used for simulating complex problems such as Simultaneous Switching Noise and Ground Bounce
The different voltage levels may be intentional variations for power savings or the result of IR drop and ground bounce