Question
According to datasheet the device protection allows up to 18mA APD current, is
this limit fix? Does it mean this device is not suitable for an APD, which
supports for example a maximum forward current of 10mA?
Answer
The overcurrent protection on ADL5317 is not programmable (unlike with the
ADL5315), but the threshold current at which the devices starts to limit varies
from the stated 18mA; it may trip as low as 14 mA and as high as 21 mA. You
should be able to use a 10mA max APD without any problem as that is well under
the absolute maximum current and under the overcurrent protection limits.