Fairchild's industry-first bi-directional logic gate optocoupler provides proven, reliable optical isolation

SAN JOSE, USA: Design engineers working with industrial communication designs need to transmit high speed data over the communication fieldbus without the risk of damaging sensitive controllers, ADCs or sensors. The current solution uses two single-channel optocouplers or other technology, like magnetic or capacitive coupling. But this does not provide the desired level of reliable isolation and immunity to EMI.

To help designers meet this challenge, Fairchild Semiconductor (NYSE: FCS) developed the FOD8012 – an industry-first, full duplex, bi-directional, logic gate optocoupler with high noise immunity as well as proven, reliable optical isolation. This bi-directional optocoupler is ideal for industrial fieldbus communications, programmable logic control, and servo control, as well as inverter, factory automation, process control and test and measurement applications.

The FOD8012 supports isolated communications of digital signals between systems without conducting ground loops or hazardous voltages. Unlike competitive devices which provide less than 0.1mm optical isolation gap, the FOD8012 features a 0.4mm (minimum) optical isolation gap for proven, reliable isolation.

The device also features a fast switching speed, up to 15Mbit/sec, and uses Fairchild’s proprietary Optoplanar packaging technology and optimized IC design to achieve high common mode rejection (CMR) of 20kV/µs minimum, allowing the device to operate in noisy industrial environments.

This high-speed logic gate optocoupler is highly integrated with two optically coupled channels arranged in a bi-directional configuration, and housed in a compact 8-pin small outline package. Each optocoupler channel consists of a high-speed AIGaAs LED, driven by a CMOS buffer IC coupled to a CMOS detector IC.

Additionally, the FOD8012 offers an extended industrial temperature range of -40 to +110ºC and a 3.3V or 5V supply voltage to facilitate logic level translation. The device’s high isolation voltage is certified by UL1577 and IEC60747-5-2 for increased reliability.

Fairchild enables customers to drive innovation in their designs by developing solutions like the FOD8012 – which is part of Fairchild’s comprehensive portfolio of high performance optocouplers. The FOD8012 offer best-in-class noise immunity resulting from its proprietary Optoplanar coplanar packaging technology. The Optoplanar technology ensures safe insulation thickness of more than 0.4 millimeters in attaining reliable high voltage isolation, certified by UL1577 and IEC60747-5-2 standards.

Priced at $3.08 each for 1K pieces, the FOD8012 sample is now available. Delivery takes eight to 10 weeks.