OP525 Equivalent & Substitute Parts

Part Overview

The OP525 is a phototransistor optical sensor manufactured by TT Electronics/Optek Technology, designed for 935nm infrared detection in a 1210 (3225 Metric) surface mount package with top view orientation. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations. The OP525 delivers a maximum collector current of 20 mA with a 30V collector-emitter breakdown voltage, suitable for infrared sensing applications requiring high sensitivity and compact form factors.

Substiute Parts

OP525

TT Electronics/Optek TechnologyIn Stock: 777OP525 Datasheet

Current PartRFQ

PT42-21B/TR8

Everlight Electronics Co LtdIn Stock: 57379PT42-21B/TR8 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The PT42-21B/TR8 manufactured by Everlight Electronics Co Ltd qualifies as a direct substitute for the OP525 based on the following critical parameters:

Electrical compatibility is established through matching voltage and current specifications: both components support 30V collector-emitter breakdown voltage and 20mA maximum collector current. Dark current specifications are identical at 100nA maximum, ensuring equivalent sensitivity characteristics. Power dissipation capacity matches at 75mW maximum.

Mechanical and packaging compatibility is confirmed through identical package designation (1210 / 3225 Metric), surface mount mounting type, and top view orientation. These parameters ensure direct PCB footprint compatibility without redesign requirements.

Wavelength compatibility exists within the near-infrared spectrum: the OP525 operates at 935nm while the PT42-21B/TR8 operates at 940nm. This 5nm difference falls within the typical spectral response overlap of phototransistor designs and maintains functional equivalence for standard infrared sensing applications.

Regulatory compliance is maintained: both components are ROHS3 compliant and REACH unaffected, meeting current environmental standards.

Parameter Comparison

Engineering Selection Recommendations

The PT42-21B/TR8 is the qualified substitute for the obsolete OP525. Selection is based on:

Electrical parameter equivalence across all critical specifications including voltage, current, and power ratings ensures direct functional replacement without circuit modification.

Package and mounting compatibility eliminates PCB redesign requirements, allowing direct component substitution in existing layouts.

Active product status of the PT42-21B/TR8 ensures long-term availability and supply chain continuity, addressing the obsolescence of the original OP525.

ROHS3 compliance and REACH unaffected status maintain regulatory alignment with current environmental standards for both original and substitute components.

The 5nm wavelength difference (935nm to 940nm) remains within acceptable tolerance for infrared sensing applications utilizing phototransistor technology, with both wavelengths operating in the near-infrared spectrum suitable for standard optical detection circuits.

Frequently Asked Questions (FAQ)

Q: Can the PT42-21B/TR8 be used as a direct replacement for the OP525 without circuit modifications?

A: Yes. The PT42-21B/TR8 matches all critical electrical parameters (voltage, current, power) and shares identical packaging (1210 / 3225 Metric), mounting type (surface mount), and orientation (top view). Direct PCB substitution is possible without redesign.

Q: What is the significance of the 5nm wavelength difference between 935nm and 940nm?

A: Both wavelengths operate within the near-infrared spectrum and fall within the typical spectral response overlap of phototransistor designs. This difference maintains functional equivalence for standard infrared sensing applications. System-specific wavelength requirements should be evaluated against application specifications.

Q: Are there differences in operating temperature ranges between the two components?

A: The OP525 operates from -40°C to 80°C, while the PT42-21B/TR8 operates from -25°C to 85°C. The substitute has a narrower low-temperature range but extends higher at the upper limit. Applications requiring operation below -25°C should reference the original OP525 specifications.

Q: What is the packaging difference between the OP525 and PT42-21B/TR8?

A: The OP525 is supplied in standard packaging, while the PT42-21B/TR8 is supplied in Tape & Reel (TR) format. Both use the identical 1210 (3225 Metric) component package. Tape & Reel packaging is standard for high-volume manufacturing and automated assembly processes.

Q: Are both components compliant with current environmental regulations?

A: Yes. Both the OP525 and PT42-21B/TR8 are ROHS3 compliant and REACH unaffected, meeting current environmental standards for electronic component manufacturing and use.

Q: Why is the OP525 listed as obsolete?

A: The OP525 is no longer manufactured by TT Electronics/Optek Technology. The PT42-21B/TR8 from Everlight Electronics Co Ltd is an active product with equivalent specifications, ensuring continued availability for applications requiring this phototransistor functionality.