Driving Avalanche Photodiodes (PCBs)
The AD500-9-8015 has the amplifier built in, you need to supply the appropriate Vcc which in the datasheet can range from 4.5V to 11V for proper operation.
The bias pin needs 100 to 240V:


  This detector requires +4.5 V to +11 V voltage supply for the
  amplifier and a high voltage supply (100-240 V) for the APD. The
  internal APD follows the gain curve published for the AD500-9-TO52-S1
  avalanche photodiode. The transimpedance amplifier provides
  differential output signals in the range of 200millivolts
  differential.


The photo multiplier needs an external amplifier circuit for proper operation