This tends to create challenges for component designers developing optocouplers in ultra-small packages.
Despite limitations, space-efficient internal design combined with surface-mount package technology allows new devices to achieve smaller overall dimensions and lower package height while meeting or surpassing the IEC 60747-5-5 specifications.
The SO6 package has an outline of 7.0mm x 3.7mm x 2.3mm allows isolation voltage of 3750V and maximum operating insulation voltage of 707Vpk. This is ideal for applications requiring insulation performance greater than the 565Vpk of existing surface-mount devices in Mini-Flat SOP (MFSOP6). To achieve comparable insulation performance, designers would otherwise have to use larger SDIP devices that measure 9.7mm x 4.6mm x 4.0mm.
In addition to improving safety performance within small device dimensions, development of optically isolated devices also targets power savings and longer device lifetimes through enhancements to the integrated LED emitter.
Gallium-arsenide (GaAs) LEDs have proved effective in many manufacturers’ product ranges, and Toshiba is now moving forward by using the latest gallium-aluminium-arsenide (GaAlAs) LED technology in its new device families. These can be driven with low currents, reducing system power consumption and supporting extended LED operating life.
Toshiba has more than 20 devices in its latest SO6 surface-mount package, for applications such as transmitting logic signals and driving intelligent power modules and driving IGBTs and MOSFETs. The range includes Non Zero-Crossing (NZC) and Zero-Crossing (ZC) triac couplers , MOSFET output devices (Photorelays), transistor output devices with AC or DC inputs, and offers a choice of standard or Darlington outputs.