The positive pole of DFB laser should be connected with Case GND, however the figure below shows that the positive pole is connected with VCCC, i wonder reason for it, and whether or this chip is suitable for this application. If it is not, is any other one suitable.
Your selected laser module is in a butterfly package with the laser anode pin connected to the case ground.
There are two ways to use this laser module with ADN2871:
1. Connecting the laser module case ground to supply Vcc. This keeps the "positive supply" design
and you can use Fig. 29 circuit directly; or
2. Using "negative supply" way to ADN2871 circuitry. In the Fig. 29 circuit, change all external Vccs to new
"negative supply" ground, change all external GNDs to -3.3V. Now, you can connect the laser module case
to negative supply ground. In this way, you may have to pay attention to the ADN2871 control/monitor signal
levels accordingly. Please note, in this case, all these DC levels are referred to -3.3V, not the ground.
Hope these are what you need.