Quad digital isolators are very low power

The ADuM1440/41/42 quad/triple/dual digital isolator ICs can be powered by as little as 1 μW in power saving mode. The devices use monolithic air core transformer technology and have a data rate up to 2 Mbits/s with 148 μA/Mbit/s per channel typical dynamic current and operation up to 125°C.

The 16-Lead QSOP packaged chips take 5.6 μA/channel quiescent current, refresh enabled, using a 3.3 V sypply. The ICs have UL 1577 recognition, a 2.5 kV rms isolation rating, and common-mode transient immunity of >25 kV/μs. They are available now for 1.98 ea/1,000.