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Fairchild optically-coupled SSRs feature 4kVrms isolation

Posted: 26 Feb 2002 ?? ?Print Version ?Bookmark and Share

Keywords:fairchild semiconductor? fairchild? ssr? solid state relay? relay?

The company's new line of SSRs consist of an AlGaAs infrared LED optically-coupled to a photovoltaic generator that drives a power MOSFET detector, and features 4kVrms isolation. The HSR312 and HSR312L are capable of switching loads of up to 250V, while the HSR412 and HSR412L handle up to 400V. Moreover, the HSR312L and HSR412L employ active current limit circuitry that enables the devices to withstand current transients.

Assembled using coplanar structure, this provides the SSRs with a wider input-to-output isolation gap and offers additional margin for passing UL1459 line cross testing, making it suitable for telecom applications such as on/off hook switches, dial-out relay switching, ring injection relays, and general switching.

It can also be used for ground start applications in speaker phones, cordless phones, answering machines, fax machines, and desktop computer modems.

The SSRs feature a dual MOSFET output configuration that allows for series or parallel connection. Parallel connection of the MOSFETs provides lower maximum on-state resistance and higher maximum load current for all models, while series connection provides lower active current limit for the HSR312L and HSR412L models.

The solid-state relays are available in a six-pin through-hole or a six-pin surface-mount DIP. The latter is available in tape-and-reels with 1,000 devices on a 33mm-diameter reel. The devices comply with the UL 1577 and 508 standards.

Pricing start at 85 (HSR312), 89 (HSR312L), 90 (HSR412), and 93 cents (HSR412L), in quantities of 1,000 units.

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