Which tools are used for on chip digital design?

I know for Cadence Encounter and Synopsys:
https://www.youtube.com/watch?v=udPMw9_rZL0

I need something light for small digital part for support of analog circuits.
This are professional tools for digital designer.

If it is small digital part, I design it manually.

There is in fact a lot of tools for digital design.

3 vendors exist

Mentor Olympus+ RealTime dedicated to small digital designs. Kinda ok tools, but I do not recommend usage, because tools are badly optimised and have tons of issues.
Synopsys IC Compiler+ DC Compiler great tool for any scale designs, good support, nice tools.
Cadence Encounter, also good tool, similar to Synopsys, depends on your knoledge and support can be rated as ok.

All this tools can help with creating your digital part from Rtl to gds and integrate it with analog part.