4N25G Optoisolator - Equivalent & Substitute Parts

Part Overview

The 4N25G is a single-channel optoisolator with transistor output manufactured by Isocom Components 2004 LTD. This component provides galvanic isolation between input and output circuits using a 6-pin DIP package. The device is classified as Active product status with full RoHS3 compliance and REACH unaffected designation. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are maintained across isolation voltage, current transfer ratio, output specifications, and package form factor.

Substiute Parts

4N25G

Isocom Components 2004 LTDIn Stock: 8624N25G Datasheet

Current PartRFQ

4N25XG

Isocom Components 2004 LTDIn Stock: 8224N25XG Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 4N25G is determined by strict equivalence across the following critical parameters:

• Isolation Voltage: 7.5Vpk (must match exactly)
• Number of Channels: 1 (single channel configuration)
• Current Transfer Ratio: Minimum 20% @ 10mA (must meet or exceed)
• Output Type: Transistor with Base (functional output topology)
• Maximum Output Voltage: 30V (must support)
• Maximum Output Current: 50mA per channel (must support)
• Vce Saturation: 500mV maximum (must meet or be lower)
• Package Form Factor: 6-DIP (0.400", 10.16mm) (mechanical compatibility)
• Operating Temperature Range: -55°C ~ 100°C (must encompass or match)
• Compliance Status: RoHS3 Compliant, REACH Unaffected (regulatory alignment)

Parts meeting all these criteria are classified as parametric equivalents and direct substitutes.

Parameter Comparison

Engineering Selection Recommendations

The 4N25XG is a direct parametric equivalent to the 4N25G. Both components share identical electrical specifications, mechanical packaging, and regulatory compliance status. Selection between these parts may be based on inventory availability, lead time, or supplier preference, as no functional or performance differentiation exists between them.

Both parts maintain Active product status and full compliance with RoHS3 and REACH requirements, ensuring suitability for current and future applications without regulatory risk.

Frequently Asked Questions (FAQ)

Q: Can the 4N25XG replace the 4N25G in existing designs? A: Yes. The 4N25XG is a direct parametric equivalent with identical isolation voltage (7.5Vpk), current transfer ratio (20% @ 10mA), output specifications (30V max, 50mA max), and 6-DIP package form factor. No circuit modifications are required.

Q: Are there any differences in compliance or certifications? A: No. Both parts carry identical RoHS3 compliance and REACH unaffected status. Moisture sensitivity level is 1 (Unlimited) for both components.

Q: What determines substitution eligibility for 4N25 series optoisolators? A: Substitution requires matching isolation voltage, channel count, current transfer ratio minimum, output type, maximum output voltage and current, Vce saturation specification, package form factor, and operating temperature range. All these parameters must align exactly or the substitute must meet or exceed performance requirements.

Q: Is the 6-DIP package compatible with standard through-hole PCB layouts? A: Yes. Both the 4N25G and 4N25XG use standard 6-DIP (0.400", 10.16mm) through-hole packaging, compatible with conventional PCB drilling and assembly processes.

Q: What is the significance of the 20% minimum current transfer ratio? A: The current transfer ratio defines the efficiency of optical coupling between input LED and output transistor. A 20% minimum at 10mA input current ensures predictable output transistor saturation and switching performance across the specified operating temperature range of -55°C to 100°C.