Voltage dropping on pcb
Assuming that the 1.8 V component uses low power, a programabble regulator LM317 can do the job. Other possible methods are:
- zener diode
- zener diode + transistor
- DC-DC voltage converter modules 

The best in my opinion is the LM317. You would need to describe the 1.8V component better so we could have an idea about the power dissipated by the regulator, maybe it would be necessary a heat sink. 

EDIT: For the requirements that you gave, I think that LM317 is the best option.







simulate this circuit &ndash; Schematic created using CircuitLab