FOD815 Equivalent & Substitute Parts

Part Overview

The FOD815 is a 5000Vrms isolation Darlington output optoisolator in 4-DIP packaging manufactured by onsemi. This component provides single-channel optical isolation with Darlington output configuration, suitable for high-voltage isolation applications requiring DC input control. The FOD815 is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Active alternatives with compatible electrical and mechanical specifications are available from Isocom Components and Lite-On Inc.

Substiute Parts

FOD815

onsemiIn Stock: 12960FOD815 Datasheet

Current PartRFQ

ISP815-1

Isocom Components 2004 LTDIn Stock: 976ISP815-1 Datasheet

SimilarRFQ

ISP815-2

Isocom Components 2004 LTDIn Stock: 1115ISP815-2 Datasheet

SimilarRFQ

ISP815-3

Isocom Components 2004 LTDIn Stock: 1024ISP815-3 Datasheet

SimilarRFQ

LTV-815

Lite-On Inc.In Stock: 45282LTV-815 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the FOD815 are qualified based on the following critical parameters that determine functional equivalence:

Mandatory Matching Criteria:

• Package / Case: 4-DIP (0.300", 7.62mm) — ensures mechanical and pin compatibility
• Number of Channels: 1 — single-channel configuration
• Output Type: Darlington — output stage topology
• Input Type: DC — control signal type
• Mounting Type: Through Hole — PCB assembly method
• Voltage - Isolation: minimum 5000Vrms — isolation rating requirement
• Current Transfer Ratio (Min): minimum 600% @ 1mA — optical coupling efficiency
• Vce Saturation (Max): 1V — output saturation voltage
• Voltage - Forward (Vf) (Typ): 1.2V — input LED forward voltage
• Current - DC Forward (If) (Max): 50mA — input LED maximum current

Allowable Parameter Variations:

• Voltage - Isolation: may exceed 5000Vrms (higher isolation is acceptable)
• Voltage - Output (Max): may exceed 35V (higher output voltage rating is acceptable)
• Current - Output / Channel: may vary if not specified in substitute
• Operating Temperature: upper limit may be lower than 105°C (105°C is maximum acceptable)
• Rise / Fall Time: 60µs, 53µs (consistent across all parts)

The ISP815 series (ISP815-1, ISP815-2, ISP815-3) from Isocom Components and LTV-815 from Lite-On Inc. meet all mandatory criteria and are direct functional equivalents.

Parameter Comparison

Engineering Selection Recommendations

LTV-815 (Lite-On Inc.) is the primary substitute for FOD815 replacement. This part maintains identical electrical specifications for isolation voltage (5000Vrms), current transfer ratio range (600% to 7500% @ 1mA), maximum output voltage (35V), and output current (80mA). LTV-815 is active in production, ROHS3 compliant, and provides direct functional equivalence with no design modifications required.

ISP815 Series (Isocom Components) — ISP815-1, ISP815-2, and ISP815-3 — are functionally equivalent alternatives. These parts exceed the isolation voltage specification (5300Vrms versus 5000Vrms) and provide higher maximum output voltage ratings (70V versus 35V). The ISP815 series maintains identical input/output characteristics, saturation voltage, and switching times. All three variants are active in production and ROHS3 compliant. The ISP815 series is suitable for applications where higher isolation voltage or output voltage headroom provides design margin.

All substitute parts are through-hole mounted in 4-DIP packaging, compatible with existing PCB layouts designed for FOD815. Selection between LTV-815 and ISP815 series depends on inventory availability and design margin requirements for isolation and output voltage specifications.

Frequently Asked Questions (FAQ)

Q: Can ISP815-1, ISP815-2, and ISP815-3 be used interchangeably with FOD815?

A: Yes. All three ISP815 variants meet the mandatory electrical and mechanical criteria for FOD815 substitution. They share identical package configuration (4-DIP), channel count (1), output type (Darlington), isolation voltage minimum (5300Vrms exceeds 5000Vrms requirement), current transfer ratio minimum (800% exceeds 600% requirement), and saturation voltage (1V). The variants differ in internal design but are electrically equivalent for FOD815 replacement applications.

Q: What is the difference between LTV-815 and ISP815 series substitutes?

A: LTV-815 provides exact electrical specification matching to FOD815 (5000Vrms isolation, 35V maximum output voltage, 600-7500% current transfer ratio range, 80mA output current). ISP815 series exceeds FOD815 specifications with higher isolation voltage (5300Vrms) and higher maximum output voltage (70V), but does not specify maximum current transfer ratio or output current. Both are functionally equivalent; ISP815 series offers additional design margin for isolation and output voltage.

Q: Are all substitute parts pin-compatible with FOD815?

A: Yes. FOD815, LTV-815, and all ISP815 variants use identical 4-DIP (0.300", 7.62mm) package configuration with through-hole mounting. Pin assignments and PCB footprints are compatible without modification.

Q: What compliance certifications apply to substitute parts?

A: LTV-815 and ISP815 series (ISP815-1, ISP815-2, ISP815-3) are ROHS3 compliant. All parts carry REACH Unaffected status and EAR99 export classification. Moisture sensitivity level is 1 (Unlimited) for all parts.

Q: Can FOD815 be replaced in existing designs without circuit modification?

A: Yes. LTV-815 provides direct replacement with identical electrical specifications. ISP815 series can be used without circuit modification; the higher isolation voltage and output voltage ratings do not require design changes and provide additional safety margin.

Q: What is the operating temperature range for substitute parts?

A: LTV-815 and ISP815 series operate from -30°C to 100°C. FOD815 specifies -30°C to 105°C. For applications requiring operation above 100°C, FOD815 specifications cannot be matched by available substitutes; design review is required.