Question
What max current can be drawn on the Visoout (PIN 12).We need to drive a
external low voltage LED on the CAN-Bus side.
Answer
Thermal considerations (power dissipated internally in the part by the DC-DC
converter and CAN transceiver) limit the maximum current for Visoout. The
ADM3053 is not specified for operation with any external circuits on Visoout.
You didn't specify the expected current to be drawn by the LED circuit. If it's
not a lot, then this may work fine in practice. Other reasons it would be OK if
the complete system has some cooling (even air) so that the maximum ambient
temperature at the ADM3053 won't be as high as 85C.