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#analog-design
Title
# analog-design
m

mmd402

03/06/2021, 7:22 AM
Newbie question. How can I create a 3v3 nfet in Magic? I am able to create a variant of 1v8 and 5v0d10v5. But I am not sure about the diffusion or contact I am supposed to use for 3v3. Or is there some other procedure?
t

Tim Edwards

03/07/2021, 12:21 AM
The
g5v0d10v5
devices are the 3.3V devices. They happen to be tolerant up to 5V.
m

mmd402

03/07/2021, 12:55 AM
Thank you for the clarification. I saw different entries in the tech file that got me confused.
#------------------------------------------------------------------------
# Supported device types
#------------------------------------------------------------------------
# device name			magic ID layer	description
#------------------------------------------------------------------------
...
# sky130_fd_pr__nfet_03v3_nvt	---		native nFET
# sky130_fd_pr__pfet_g5v0d10v5	mvpfet		thickox pFET
# sky130_fd_pr__nfet_g5v0d10v5	mvnfet		thickox nFET
...
t

Tim Edwards

03/07/2021, 12:58 AM
The "native" nFET has an undoped channel and a threshold voltage of near zero, so it is a different device.
m

mmd402

03/07/2021, 8:36 PM
Thank You. I am still processing the information you provided and filling in my knowledge gaps. 🙂