EL817(M) Optoisolator Equivalent & Substitute Parts

Part Overview

The EL817(M) is a 5000Vrms isolation optoisolator with transistor output manufactured by Everlight Electronics Co Ltd. This single-channel device operates in DC input mode with a 4-DIP through-hole package and is classified as Active product status. The component is ROHS3 compliant with MSL rating of 1 (Unlimited).

Substitute parts are identified when equivalent electrical performance and mechanical compatibility are maintained across the allowed parameter specifications for optoisolator transistor output devices in this isolation voltage class and package format.

Substiute Parts

EL817(M)

Everlight Electronics Co LtdIn Stock: 1123EL817(M) Datasheet

Current PartRFQ

FOD817300W

Fairchild SemiconductorIn Stock: 1131FOD817300W Datasheet

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FOD817A300W

onsemiIn Stock: 9333FOD817A300W Datasheet

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FOD817B300W

onsemiIn Stock: 1445FOD817B300W Datasheet

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FOD817C300W

onsemiIn Stock: 86369FOD817C300W Datasheet

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FOD817D300W

onsemiIn Stock: 3170FOD817D300W Datasheet

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140817141010

Würth ElektronikIn Stock: 1036140817141010 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the EL817(M) are classified based on strict electrical and mechanical parameter alignment. The following criteria determine substitution eligibility:

Primary Matching Criteria:

• Voltage - Isolation: 5000Vrms (mandatory)
• Number of Channels: 1 (mandatory)
• Output Type: Transistor (mandatory)
• Input Type: DC (mandatory)
• Package / Case: 4-DIP (0.400", 10.16mm) (mandatory)
• Mounting Type: Through Hole (mandatory)
• Operating Temperature Range: -55°C ~ 110°C (mandatory)
• Vce Saturation (Max): 200mV (mandatory)
• Current - Output / Channel: 50mA (mandatory)

Secondary Matching Criteria:

• Current Transfer Ratio range must encompass or fall within the EL817(M) specification of 50% to 600% @ 5mA
• Voltage - Forward (Vf) (Typ): 1.2V ±0.04V acceptable
• Current - DC Forward (If) (Max): 50-60mA acceptable
• Rise / Fall Time: 3-4µs acceptable

Substitute parts are grouped by Current Transfer Ratio performance bands to enable selection based on application requirements within the allowed parameter envelope.

Parameter Comparison

Engineering Selection Recommendations

All listed substitute parts maintain Active product status and ROHS3 compliance, ensuring long-term availability and regulatory alignment with the EL817(M).

Direct Functional Equivalents (Identical CTR Range): FOD817300W and 140817141010 provide identical Current Transfer Ratio specifications (50% to 600% @ 5mA) to the EL817(M). These parts are functionally interchangeable for applications requiring the full CTR performance envelope. FOD817300W offers higher maximum output voltage (70V vs 35V). The 140817141010 maintains the 35V output voltage specification matching the EL817(M).

Performance-Graded Alternatives (Narrower CTR Ranges): FOD817A300W, FOD817B300W, FOD817C300W, and FOD817D300W are onsemi variants with progressively higher minimum CTR specifications. These parts operate within the EL817(M) CTR envelope but with tighter performance bands. Selection depends on application requirements for minimum current transfer efficiency.

Voltage Output Consideration: FOD817 series parts (FOD817300W, FOD817A300W, FOD817B300W, FOD817C300W, FOD817D300W) support 70V maximum output voltage compared to 35V for EL817(M) and 140817141010. Applications requiring higher output voltage ratings benefit from FOD817 selection.

Packaging and Compliance: All parts are 4-DIP through-hole packages with identical footprint dimensions (0.400", 10.16mm). All substitute parts are ROHS3 compliant. onsemi FOD817 variants carry REACH Unaffected status with Not Applicable MSL rating. Würth Elektronik 140817141010 maintains MSL 1 (Unlimited) matching the EL817(M).

Frequently Asked Questions (FAQ)

Q: Can FOD817A300W replace EL817(M) in all applications?

A: FOD817A300W is electrically compatible within the 4-DIP package format and 5000Vrms isolation specification. However, its Current Transfer Ratio range (80% to 160% @ 5mA) is narrower than EL817(M) (50% to 600% @ 5mA). Applications requiring minimum CTR below 80% or maximum CTR above 160% require alternative selection.

Q: What is the difference between FOD817A300W, FOD817B300W, FOD817C300W, and FOD817D300W?

A: These onsemi variants differ only in Current Transfer Ratio performance bands. FOD817A300W: 80-160%, FOD817B300W: 130-260%, FOD817C300W: 200-400%, FOD817D300W: 300-600%. All other electrical and mechanical parameters are identical. Selection is based on application requirements for minimum and maximum current transfer efficiency.

Q: Is the 70V output voltage of FOD817 series a limitation or advantage?

A: The 70V maximum output voltage of FOD817 series is higher than EL817(M) (35V). This provides greater design margin for applications with higher output voltage requirements. For applications limited to 35V output, both EL817(M) and 140817141010 are suitable.

Q: Are all substitute parts available in the same packaging format?

A: All substitute parts use 4-DIP (0.400", 10.16mm) through-hole packages with identical footprint dimensions. PCB layout and mechanical mounting are directly compatible. FOD817 series parts are supplied in Tube packaging, while 140817141010 is also supplied in Tube packaging.

Q: Which substitute part has the highest inventory availability?

A: FOD817C300W (onsemi) has the highest inventory at 86,301 pieces. FOD817A300W (onsemi) has 9,265 pieces. Other parts range from 1,024 to 3,097 pieces. Inventory levels are subject to change.

Q: Can EL817(M) be replaced with 140817141010 without circuit modification?

A: Yes. The 140817141010 (Würth Elektronik) maintains identical electrical specifications for isolation voltage, CTR range (50-600% @ 5mA), output voltage (35V), and operating temperature (-55°C ~ 110°C). The 4-DIP package footprint is identical. No circuit modification is required.

Q: What is the significance of Current Transfer Ratio (CTR) in optoisolator selection?

A: Current Transfer Ratio defines the ratio of output collector current to input LED current. Higher CTR indicates greater optical coupling efficiency. Applications requiring specific output current levels at given input currents must match CTR specifications. Narrower CTR ranges (FOD817 variants) provide tighter performance control compared to wider ranges (EL817(M), FOD817300W, 140817141010).