ILQ2 Optoisolator Equivalent & Substitute Parts

Part Overview

The ILQ2 is a 4-channel optoisolator with transistor output manufactured by Vishay Semiconductor Opto Division. It provides 5300Vrms isolation voltage in a 16-DIP package and is designed for applications requiring high-voltage galvanic isolation with multiple independent channels. The product is currently in Last Time Buy status, making identification of equivalent alternatives essential for long-term design continuity and supply chain planning.

Substiute Parts

ILQ2

Vishay Semiconductor Opto DivisionIn Stock: 1803ILQ2 Datasheet

Current PartRFQ

ILQ2

Isocom Components 2004 LTDIn Stock: 1791ILQ2 Datasheet

MFR RecommendedRFQ

ILQ2X

Isocom Components 2004 LTDIn Stock: 1112ILQ2X Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ILQ2 is constrained by the following critical parameters that must be maintained for functional equivalence:

Mandatory Matching Parameters:

• Voltage - Isolation: 5300Vrms (electrical requirement for galvanic isolation level)
• Output Type: Transistor (functional architecture)
• Package / Case: 16-DIP (0.300", 7.62mm) (mechanical and pin compatibility)
• Current Transfer Ratio range: 100% - 500% @ 10mA (optical coupling efficiency)
• Voltage - Output (Max): 70V (output stage rating)
• Current - Output / Channel: 50mA (output drive capability)

Allowable Variation Parameters:

• Number of Channels: The ILQ2 features 4 channels. Single-channel alternatives (ILQ2, ILQ2X from Isocom) are functionally equivalent on a per-channel basis but represent a different channel configuration. Selection depends on application requirements.
• Operating Temperature: The ILQ2 operates -40°C ~ 100°C. Alternatives with -25°C ~ 100°C range have a narrower lower temperature specification but maintain the upper limit.
• Turn On / Turn Off Time and Rise / Fall Time: Minor timing variations are acceptable within the optoisolator functional class.

Parameter Comparison

Engineering Selection Recommendations

Primary Consideration: Channel Configuration

The ILQ2 (Vishay) is a 4-channel device, while both Isocom alternatives (ILQ2 and ILQ2X) are single-channel devices. Direct 1:1 substitution is not possible without circuit redesign. Applications requiring 4 independent isolated channels must either:

• Retain the Vishay ILQ2 while supply is available (Last Time Buy status)
• Redesign using four single-channel Isocom ILQ2 or ILQ2X devices in parallel

For Single-Channel Isolation Requirements:

Both Isocom ILQ2 and ILQ2X are functionally equivalent substitutes. Selection between them is based on:

• ILQ2 (Isocom): Active product status with standard packaging
• ILQ2X (Isocom): Active product status with Tube packaging, higher inventory availability (1050 Pcs vs 1739 Pcs for Vishay)

Temperature Range Consideration:

The Isocom alternatives specify -25°C ~ 100°C operating temperature, compared to the Vishay ILQ2 specification of -40°C ~ 100°C. Applications requiring operation below -25°C must retain the Vishay device or identify alternative optoisolator families with extended low-temperature ratings.

Compliance and Regulatory Status:

All three parts maintain ROHS3 compliance, REACH Unaffected status, and identical ECCN/HTSUS classifications, ensuring regulatory equivalence for procurement and supply chain purposes.

Frequently Asked Questions (FAQ)

Q: Can I use a single Isocom ILQ2 or ILQ2X to replace the Vishay ILQ2?

A: No. The Vishay ILQ2 contains 4 independent channels in a single package, while Isocom alternatives are single-channel devices. A direct 1:1 substitution is not possible. Applications requiring 4 isolated channels must either use four separate Isocom devices or identify a different 4-channel optoisolator family.

Q: What is the difference between Isocom ILQ2 and ILQ2X?

A: Both devices are electrically identical with matching isolation voltage (5300Vrms), current transfer ratio (100%-500%), output ratings (70V, 50mA), and operating temperature (-25°C ~ 100°C). The primary difference is packaging: ILQ2X is supplied in Tube packaging, while ILQ2 packaging is not specified. Selection should be based on inventory availability and packaging requirements for your assembly process.

Q: Why does the Isocom ILQ2 have a narrower operating temperature range (-25°C vs -40°C minimum)?

A: Operating temperature range is a specified characteristic of each device design. The Isocom ILQ2 and ILQ2X are rated to -25°C minimum, while the Vishay ILQ2 extends to -40°C. Applications requiring operation below -25°C must use the Vishay device or select alternative optoisolator products with extended low-temperature specifications.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use the 16-DIP (0.300", 7.62mm) package, ensuring mechanical and pin-level compatibility. However, channel configuration differences (4-channel vs 1-channel) require circuit redesign if substituting the Vishay 4-channel device with single-channel alternatives.

Q: What does "Last Time Buy" status mean for the Vishay ILQ2?

A: Last Time Buy indicates that Vishay will discontinue this product after current inventory is depleted. No new production runs are planned. Designers should evaluate long-term supply requirements and consider migration to active alternatives (Isocom ILQ2 or ILQ2X) or identify replacement optoisolator families for future designs.

Q: Are there any electrical performance differences I should consider?

A: Minor differences exist in forward voltage (Vishay 1.25V vs Isocom 1.2V) and maximum forward current (Vishay 60mA vs Isocom 50mA). These variations are within typical optoisolator tolerance ranges and do not affect functional equivalence for standard isolation applications. Circuit designs should account for these specifications during input LED current budgeting.