AD7291 does what on AD-FMCOMMS3-EBZ with AD9361?

Sorry, I need to fish through more datasheets, but quickly looking at diagrams of the FMCOMMS3-EBZ to FPGA reference builds, it looks like the A/D function is straight from the AD9361 to the FPGA for 12 bit samples.  I don't see where/how the AD7291 comes into play in the signal RF to Digital chain?  I just see that it provides the temperature of chip...


What role does the AD7291 play on this board, where should I be looking to understand this.