Tiny photo relays from Toshiba are 2mm long

The new part, TLP3476S, is in a 1.5mm high (max) S-VSON4T package, has a maximum on-resistance of 1.5Ω, can carry 400mA (ac or dc) and isolates up to 500Vrms.

3mA is the maximum LED drive needed to operate the device (30mA abs max), and operation is across -40 to 110°C.

Applications are expected in semiconductor testers, probe cards and other instrumentation.

The TLP3476S product page can be found here