I would like to hook up an ADuM7440 to convert 4 signals from NEGCMOS [Logic ‘1’ = 0V, Logic ‘0’ = -5V] to normal +3.3V LVCMOS [Logic ‘1’ = +3.3V, Logic ‘0’ = 0V] on the other side.
VDD1 - GND
GND1 - -5V
VDD2 - +3.3V
GND2 - GND
Is this is acceptable? The datasheet seems to imply that only positive rails are acceptable, even though the 1kV of digital isolation should be sufficient.