H11A3 Optoisolator Equivalent & Substitute Parts

Part Overview

The H11A3 is a 5000Vrms optoisolator transistor with base output in a 6-DIP package manufactured by Lite-On Inc. This component provides galvanic isolation for DC input signals with transistor output capability. The H11A3 is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Substitute parts must maintain compatibility across isolation voltage, channel configuration, package type, and output characteristics.

Substiute Parts

H11A3

Lite-On Inc.In Stock: 1460H11A3 Datasheet

Current PartRFQ

4N26M

onsemiIn Stock: 509034N26M Datasheet

MFR RecommendedRFQ

H11A3-V

Everlight Electronics Co LtdIn Stock: 844H11A3-V Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the H11A3 is determined by the following critical parameters:

Primary Compatibility Criteria:

• Package type: 6-DIP (0.300", 7.62mm) through-hole mounting
• Output configuration: Transistor with base
• Input type: DC
• Number of channels: 1
• Current Transfer Ratio minimum: 20% @ 10mA
• Voltage - Forward (Vf): 1.2V nominal

Isolation Voltage Consideration: The H11A3 specifies 5000Vrms isolation. Substitute parts with equal or greater isolation voltage are acceptable. Parts with lower isolation voltage do not meet the isolation requirement and are not suitable substitutes.

Output Voltage and Current: The H11A3 supports 30V maximum output voltage and 150mA per channel. Substitute parts must support these output specifications or higher ratings.

Temperature Range: The H11A3 operates from -55°C to 100°C. Substitute parts with equal or wider temperature ranges are acceptable.

Parameter Comparison

Engineering Selection Recommendations

H11A3-V (Everlight Electronics Co Ltd): This part is the primary substitute for the H11A3. It maintains identical isolation voltage (5000Vrms), matching current transfer ratio, equivalent forward voltage, and identical Vce saturation. The H11A3-V is active in production with ROHS3 compliance and extends the operating temperature range to 110°C. The maximum output voltage rating increases to 80V, providing additional design margin. This part is recommended for direct replacement in new designs.

4N26M (onsemi): This part is an alternative substitute with active product status and ROHS3 compliance. The isolation voltage is 4170Vrms, which is lower than the H11A3 specification of 5000Vrms. The 4N26M maintains the same current transfer ratio, output voltage maximum, and forward voltage characteristics. The Vce saturation is 500mV compared to 400mV for the H11A3. The operating temperature range is -40°C to 100°C, which does not extend to the -55°C minimum of the H11A3. Selection of the 4N26M requires confirmation that the reduced isolation voltage and narrower temperature range are acceptable for the application.

Frequently Asked Questions (FAQ)

Q: Can the H11A3-V directly replace the H11A3 in existing designs? A: Yes. The H11A3-V maintains the same isolation voltage (5000Vrms), current transfer ratio (20% @ 10mA), forward voltage (1.2V), and Vce saturation (400mV). Both use the 6-DIP through-hole package. The H11A3-V extends the upper operating temperature to 110°C and increases maximum output voltage to 80V, providing enhanced performance margins.

Q: Why is the 4N26M listed as a substitute if its isolation voltage is lower? A: The 4N26M is included as an alternative option. However, its 4170Vrms isolation voltage is below the H11A3 specification of 5000Vrms. This part is suitable only for applications where the reduced isolation voltage meets system requirements. The narrower temperature range (-40°C to 100°C) also excludes operation at -55°C.

Q: Are all three parts pin-compatible? A: Yes. All three parts use the 6-DIP (0.300", 7.62mm) through-hole package with identical pinout for transistor-with-base optoisolators. Direct socket substitution is possible without PCB modification.

Q: What compliance certifications apply to substitute parts? A: Both the 4N26M and H11A3-V are ROHS3 compliant. The 4N26M is REACH unaffected. The H11A3-V carries ROHS3 compliance and maintains the same MSL rating (1 - Unlimited) as the original H11A3.

Q: Which substitute should be selected for new production? A: The H11A3-V is the recommended primary substitute, as it matches all critical electrical parameters of the H11A3 and is actively manufactured. The 4N26M may be considered only if the application requirements permit reduced isolation voltage and narrower temperature range operation.