Getting 3.6V, 1.8V, and 1.1V from 12V using LM117 or LM317
That regulator will not provide output voltages below 1.25V.

The device uses an internal 1.25V reference voltage and the output voltage (via R1 and R2) is potted down to equal 1.25V. If the desired output voltage is less than 1.25V then it doesn't work.

AD8605 op-amp regulator for supplying 30mA at 1.1V: -