Vishay K825P Optoisolator - Equivalent & Substitute Parts

Part Overview

The Vishay K825P is a 2-channel optoisolator with Darlington output, rated for 5300Vrms isolation voltage. This component is classified as Last Time Buy, indicating discontinued production with limited remaining inventory. Finding qualified substitute parts is essential for ongoing design support and long-term supply chain continuity. The K825P serves applications requiring high-voltage isolation with DC input and Darlington output configuration in 8-DIP through-hole packaging.

Substiute Parts

K825P

Vishay Semiconductor Opto DivisionIn Stock: 20208K825P Datasheet

Current PartRFQ

EL825

Everlight Electronics Co LtdIn Stock: 993EL825 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the K825P is determined by the following critical parameters:

• Number of Channels: Must be 2 channels
• Package / Case: Must be 8-DIP (0.300", 7.62mm) for mechanical compatibility
• Mounting Type: Must be Through Hole
• Output Type: Must be Darlington
• Input Type: Must be DC
• Voltage - Isolation: Minimum 5000Vrms (K825P rated at 5300Vrms)
• Current Transfer Ratio (Min): Minimum 600% @ 1mA
• Current - Output / Channel: Minimum 80mA
• Voltage - Output (Max): Minimum 35V
• RoHS Status: ROHS3 Compliant

The Everlight EL825 meets all substitution criteria, maintaining functional equivalence across isolation voltage, channel configuration, output characteristics, and package specifications.

Parameter Comparison

Engineering Selection Recommendations

The Everlight EL825 is a qualified substitute for the Vishay K825P based on the following factors:

• Functional Equivalence: Both parts maintain 2-channel Darlington output configuration with identical package and mounting specifications.
• Isolation Voltage: The EL825 5000Vrms rating meets the minimum isolation requirement, with K825P providing 300Vrms additional margin.
• Electrical Performance: Current transfer ratio, forward voltage, and output current specifications are identical. The EL825 provides superior maximum output voltage (40V vs 35V) and wider operating temperature range (-55°C to 110°C vs -40°C to 100°C).
• Compliance: Both parts are ROHS3 Compliant and carry equivalent regulatory certifications (EAR99, HTSUS 8541.49.8000).
• Product Status: The EL825 is Active, providing ongoing availability and supply chain stability compared to the K825P Last Time Buy status.

Frequently Asked Questions (FAQ)

Q: Can the Everlight EL825 directly replace the Vishay K825P in existing designs?

A: Yes. Both parts share identical 8-DIP package dimensions, through-hole mounting, 2-channel configuration, and core electrical specifications (600% minimum CTR, 80mA output current, 1.2V forward voltage). Pin-to-pin compatibility is maintained.

Q: What are the key differences between these parts?

A: The EL825 provides 5000Vrms isolation versus K825P's 5300Vrms. The EL825 has a wider operating temperature range (-55°C to 110°C vs -40°C to 100°C) and higher maximum output voltage (40V vs 35V). The K825P specifies tighter Vce saturation (100mV vs 1V).

Q: Is the lower isolation voltage of the EL825 acceptable?

A: The EL825's 5000Vrms isolation exceeds the minimum substitution requirement. Application-specific isolation voltage margins must be verified against circuit design specifications.

Q: Are there any thermal or temperature considerations?

A: The EL825 supports a wider operating temperature range. Applications operating near the K825P's upper limit (100°C) benefit from the EL825's extended range to 110°C.

Q: What is the impact of the Vce saturation difference?

A: The K825P specifies 100mV maximum saturation versus the EL825's 1V. Applications with tight saturation voltage requirements should verify the EL825's performance against circuit design margins.

Q: Are both parts RoHS compliant?

A: Yes. Both the K825P and EL825 are ROHS3 Compliant with identical regulatory classifications.