Looking at all the devices, there are the normal 1.8v devices, and then there are 3.3V, 5V devices, but only NMOS and g5v0d10v5 devices in NMOS and PMOS, and then the extended drain ones. Am I correct that the only difference between all the non-extended drain ones is the VT inserts? Both 3.3 and 5 say "The native device is constructed by blocking out all VT implants" though. And there are no 3.3v pmos? So if you want to do analog design with more than 1.8v you pretty much need to go for the g5v0d10v5 ones? Is the downside that they are slower than the 1.8v devices, or what's the deal here?

g5v0d10v5 devices are good enough for analog design. 018 devices with minimum L are terrible for voltage gain, after all. But if you design a ring oscillator with 5V devices and 3 V VDD, and another one with 1.8V devices and 1.8 V VDD, both with minimum length (500 nm and 150 nm, respectively), the latter will be faster.

I would expect the 1.8V version would have a higher gm than the 5V version coz of thinner oxide and constant electric field scaling. But as you mentioned possibly have worse ro performance. It would be an interesting experiment to try and compare the results

I don't know if they have the same gm/id characteristics... I would need to test this.

@Pepijn de Vos: There is only one thick oxide mask, and the devices are rated for up to 5V, but the HVL library standard cell library is rated to run at 3.3V, and the I/O cells will run at any voltage from 1.8V to 5.5V, which we have verified on the bench. A few of the devices are rated for a narrower range, and (I think) that's why there are a few devices that are specified as "3.3V" devices. Otherwise, anything in the range of 3.3 to 5.5V is a thick oxide device.