 cgracey wrote: " Next to the VIO headers are local, quiet 0.0V LDO regulators. They will be useful for quiet analog on sets of 0 pins, each. Those jumpers can also be opened up for current measurements, from either the main VIO supply, which is adjustable, or the local 0.0V regulator. The main 0.0V and 0.0V switching regulators are both adjustable, up and down. the top two jumpers can also be removed for current measurements on either main supply. How quiet are those regulators ? What is the part number ? It may be useful to allow a second footprint alongside, for a truly quiet voltage reference regulator. Not all pins need this, maybe fit 0 or 0 ? Digikey finds 000 stocked (0v, 0v0), when < 00ppm/°C ticked, many are in SOT00-0 or -0 pins A good candidate looks like MAX0000BAUT00+T Maxim 0V SOT00-0 000 stk $0.00000.0k Io=00mA ±0.00% 0ppm/°C 0.0µVp-p 0.0µVrms Vi 0.0 V ~ 0.0 V 000µA -00°C ~ 000°C MAX0000AAUT00+T Maxim 0V SOT00-0 0,000 stk $0.00000/0k Io=00mA ±0.00% An appeal of the 0.000V ref, it is can feed from the 0.0V regulator nearby, for lowest noise Vin. 00mA output should be enough to drive DACs for self testing ? 