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onsemi FOD817AS — Optoisolators

onsemi FOD817AS Optoisolator, 5000Vrms, Transistor Output

MPNFOD817AS
Active

onsemi FOD817AS single-channel DC-input transistor-output optocoupler, 5000Vrms isolation, 80-160% CTR at 5mA, 4-SMD Gull Wing package, -55°C to 110°C, Active.

$0.5400Ref. price · indicative, final on quote
Packaging4-SMD, Gull Wing
RoHSROHS3 Compliant
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

FOD817AS specifications
ParameterValue
Input typeDC
Output typeTransistor
MountingSurface Mount
Voltage - isolation5000Vrms
Voltage - output70V
Voltage - forward (Vf)1.2V
Current - output (Channel)50mA
Current transfer ratio160% @ 5mA
Current - DC forward (If)50 mA
Operating temperature-55°C ~ 110°C
PackageTube
Case4-SMD, Gull Wing
Channels1
Vce saturation200mV
Rise (Fall time)4µs, 3µs

Product details

5000Vrms isolation and CTR window for BOM fit

The FOD817AS provides 5000Vrms galvanic isolation between a DC input and a transistor output — sufficient for reinforced insulation in mains-referenced control circuits per IEC 60950-1 reinforced grade. Current transfer ratio is specified as a min/max window of 80% to 160% at If=5mA, not a single typical value — the 2:1 spread means the designer must budget for the low end in the load resistor calculation and the high end for saturation margin. Output transistor handles up to 70V collector-emitter and 50mA continuous, with a 200mV Vce(sat) max at rated current — this drives standard 5V or 24V logic inputs directly without a buffer stage.

Switching speed and temperature range for industrial duty

Typical rise and fall times of 4µs and 3µs respectively limit the useful data rate to roughly 100 kbps — adequate for 50/60 Hz zero-cross detection, PLC input isolation, or status feedback, but not for high-speed serial links. Operating temperature spans -55°C to 110°C, covering the full industrial range and reaching into automotive under-hood ambient where the junction temperature stays below the 150°C abs-max typical for this class. The 1.2V typical forward voltage at 5mA input current aligns with standard 3.3V or 5V logic outputs — the series resistor calculation uses Vf=1.2V as the drop across the LED, leaving the remainder across the current-limiting resistor.

Active lifecycle and compliance status

Sourced through independent distribution channels; availability and current pricing confirmed against an RFQ for the specific BOM quantity.

Frequently asked questions

What is the closest functional second-source for FOD817AS?

The FODM1009 is the nearest peer: same DC input, single-channel transistor output, surface-mount 4-pin package, and 5000Vrms isolation. Key differences are a wider CTR spread (not specified as a min/max window in the same way), 300mV Vce(sat) vs 200mV, and slightly slower 5.7µs/8.5µs rise/fall times. The FOD817AS offers tighter saturation and faster edges for the same isolation class.